DESC:Field of Invention:
The present invention is in field of drug administration device for administration of an injectable substance. More particularly, the present invention is in field of wearable drug administration devices that also facilitates controlled administration of injectable substance.

Background of Invention:
Intravenous (IV) administration avoids the first-pass drug effect resulting in direct entry of drug into the systemic circulation and consequently an immediate drug effect. For many years, the vial and syringe were the standard means of delivering drug substances intravenously. However, the fact that not all patients were comfortable with this method has serious implications for compliance and disease control. Hence, Auto-injections pens were developed.

Auto-injection pens provide patients with more freedom to manage their everyday injectable drug administration when compared to the “vial and syringe” system, reducing dependence on other people for injecting medication and improving overall quality of life.

Use of auto-injection pens have changed the course of treatment by increasing awareness about diseases among the patients and emphasizing need for adherence to medication. However, there are many shortcomings in the current auto-injection pen devices, including difficulty in handling lengthy and bulky self-injectable devices, mostly encountered by young adults and patients with smaller hand span. In particular, it is inconvenient for self-administration where the user has to hold muscular folds with one hand and apply the injection perpendicularly at the site of injection using the other hand.

Other issues with use of the auto-injection pens include need for priming the pen before use, incorrect use of the dose-dial, greater force required to push the administration button, no indication of completion of dose administration and withdrawal of needle from the injection site before complete administration of the full dosage.

These limitations in the drug administration devices lead to poor patient adherence and reduced treatment efficacy. Further, incomplete administration of prescribed drug dosage may prove fatal in many of the life-threatening conditions, requiring emergency medical intervention.

With an increasing number of patients, both young and old, requiring access to self-injectable drugs, there is a growing need for developing more efficient, compact and easily manageable self-administration devices for delivering injectable substances. Hence, it is the intention of the current inventors to provide a method and device for more efficient administration of medication, particularly self-administered medications, particularly beneficial for young patients.

Various inventors had developed a compact, easily portable system which could easily administer medicaments. US6792306, for instance, discloses an electrokinetic drug administration device which is designed to be functionalised using a finger. Another example is the device disclosed in US20090163807. The device as disclosed in US ‘807 is finger actuated transducer device for therapeutic application.

Hence, the current inventors, therefore, propose a new finger mounted device for administration of therapeutic substance which provides easy, effective and controlled administration of injectable substance.

Summary of Invention:
In an aspect, the invention provides a wearable drug administration device for administration of injectable substances which gives greater accuracy and ease of use for self-administration, specifically for young adults and patients with smaller hand span.
Further, the invention provides wearable drug administration device for controlled administration of injectable substances which is mechanically enabled, thereby eliminating use of battery or external power source.

Furthermore, the invention provides a wearable drug administration device for controlled administration of injectable substances with self-triggering mechanism.

In another aspect, the invention provides a novel drug-pod design to be used with the wearable drug administration device.

In yet another aspect, the invention further provides a drug-pod casing for holding multitude of drug-pods.

Brief Description of Drawings:
Fig. 1 illustrates a block diagram of various components of the drug administration system.

Fig. 2 illustrates the side view of the device of the invention.

Fig. 3 illustrates the top view of the device of the invention.

Fig. 4 illustrates a holder with finger mounting position.

Fig. 5 illustrates the drug-pod casing for holding drug pods.

Fig. 6 illustrates flap and trigger mechanism for self-triggering of the device.

Fig. 7 illustrates the drug pods (208) which could be used with the device of the invention.

Fig. 8 illustrates the drug pods (208) which are further provided with a soft silicone head (601) or (602).

Detailed Description of the Drawings:
As illustrated in Fig. 2 and Fig. 3, the wearable drug administration device (200) comprises of a needle insertion unit (201) which is attached at base of a drug-pod chamber (202) through a centrally placed insertion point. The drug-pod chamber (202) is made up of smooth walls, and is configured for housing a drug-pod (208).

A drug-pod pusher head (203) is connected to a drug-pod pusher connecting rod (204) and is inserted through an insertion point placed opposite to the insertion point for needle insertion unit (201). The drug-pod pusher (203) conforms to the shape of the drug-pod chamber (202) and is configured to press the drug-pod (208). The drug-pod pusher (203) features a curvature on top end which conforms to the shape of the drug-pod chamber (202). Further, the walls of the drug-pod pusher have a smooth finish, which allows easy movement of the drug-pod pusher (203) in the drug-pod chamber (202). When the drug-pod pusher (203) is depressed, the force of depression is transferred to the drug-pod (208) which interacts with the needle insertion unit (201) which results in puncturing of the drug-pod (208) for administration of the drug substance contained in the drug-pod (208).

The drug-pod Pushing road (204) is connected to the drug-pod pusher (203). The drug-pod pusher rod is connected to an energy-storage element (205).

The device of the invention further comprises a dosage setting knob (206). The dosage setting knob (206) is conjoined with a dosage setting mechanism which includes a visual indicator for determining the position of the dosage setting knob (206) for a set value of drug dose and other various similar feedback elements such as visual, audio feedbacks etc., to provide a device response to various user interactions such as dosage setting, device activation, dosage administration, completion of drug administration, status of drug-pod in the chamber etc. The dosage setting mechanism comprises a drivetrain having gears (211) to transfer the dosage setting knob (206) motion to the movement of drug-pod pusher (203). The gear train system (211), preferably worm gears or pin slot mechanism, is used to transfer the knob (206) motion into perpendicular direction of motion.

the drug-pod chamber has a drug-pod lid, also referred to as lid, (207) with an inner profile matching the barrel curvature. The said lid (207) when closed, presses the drug-pod (208) loaded in the drug-pod chamber (202) such that the drug-pod occupies all the available space in the barrel completely. The said lid (207) rises the pressure inside the drug-pod (208) such that equivalent pressure is required to push the drug to the tip of the needle when the needle punctures the drug-pod (208). The lid (207) is, further, configured to increase the pressure inside the chamber (202) ensuring sufficient pressure to prime the needle insertion unit (201).

The drug-pod (208) of the present invention as shown in Figure 1, are designed to carry injectable substances which can be used with the wearable administration device (200) as described above. The drug-pod (208) can be made of soft gelatine capsule material in different colours, shapes, dimensions and volumes, which are defined by the dosage of injectable substance it carries and compatibility for use with the wearable device (200).

Further, the device (200) features a self-triggering mechanism which comprises of a button (209) on the device head as shown in Fig. 2, which interacts with the body of the user when pressing the device to the injection site. This self-triggering mechanism of the device (200) provides a mechanically enabled drug administration system which eliminates need of battery or external power sources.

Furthermore, the device (200) of the invention contains a self-locking mechanism (210) which allows for easy movement of the drug-pod pusher (203) during dosage setting and is restricted motion in other direction.

In one of the embodiments, the device (200) of the invention is further provided with a finger mounting position (410). Said finger mounting position (410) may be a padded recession which enhances the grip and eases operation of the device (200)

Fig. 5 illustrates a drug-pod casing (500). The drug pod casing (500) is a box which encompasses plurality of drug-pod holders (502) for containing drug-pods (208). The drug-pod casing is further designed to hold the needles in needle holders (501). Said drug pod casing (500) could be manufactured form any material which is resistant to environmental factors and strong enough to protect the drug-pods (208) and drug pod needles from environmental factors as well as mechanical damage.

Fig. 6 illustrates a flap (301) and trigger (302). The Flap-and-trigger mechanism is the self-triggering mechanism for triggering the device. This is achieved by using a hollow ellipsoid shaped flap (301) that partially covers the bottom area of the device and along the curvature of the device head, that comes in contact with the body while injecting. This hollow ellipsoid flap curves along the device head to establish contact with the trigger button (209) by means of small trigger rod (302) provided at the end of the flap. The flap (301) pushes the trigger rod (302) which in turn activates the trigger button (209), thereby administrating the drug to the user.

Figs. 7 illustrate the drug pod (208). The said drug pods can be made of soft gelatine capsule material in different colours, shapes, dimensions and volumes, which are defined by the dosage of injectable substance it carries and compatibility for use with the wearable device (200). The shape of the drug-pod (208) ensures correct placement of the pod in the drug-pod chamber (202) and alignment with the drug-pod pusher head (203) for facilitating complete dispensing of the injectable substance.

Further, as illustrated in Fig. 8, The said pods (208), may be provided with a head (601) or (602) which is made of soft silicone. The head (601) or (602) to enable integration with the needle in the needle insertion unit (201) of the wearable device (200) and also to permit pressure driven priming.

Detailed Description of the Invention:
Described herein is a drug administration system comprising of a wearable finger-mounted injection device with self-triggering mechanism for controlled administration of injectable substances.

Accordingly, the present invention discloses a novel compact design of an injection device which is wearable and finger-mounted for controlled administration of injectable substances designed to be operated using a single hand with greater ease and accuracy, as compared to a vial and syringe administration system, so that the other hand is free for holding the skin fold at the site of administration during injection administration., especially, during self-administration of the injection by the patient.

The novel device design enables easy administration of vaccines and other injectable substances to infants, children, young adults and geriatric subjects, with greater accuracy and control. Specifically, this wearable injection device helps to abate needle phobia among patients with fear of needles which is commonly associated with the vial and syringe administration system.

Additionally, the compact design of the wearable injection device aids in discreet self-administration of injectable substances by patients, thereby positively impacting psychological factors for patient medication adherence.

Furthermore, the wearable finger-mounted drug administration device of the invention is provided with a mechanical flow-rate controller which facilitates administration of micro-volumes of the drug dosage, in the order of 0.0025 ml, which is lower than the drug dosage deliverable with auto-injection pens available in market.
The wearable finger-mounted drug administration device of invention is, further, provided with the self-triggering mechanism which eliminates need for additional force to push an administration button to initiate drug injection and also prevents accidental release of injectable substance from the administration device. The self-triggering mechanism involves pressing the device to the injection site which activates a button on the tip of the device by interacting with the injection site on the body. This button is self-retracting when the administration device is removed from injection site and contact with the body is disconnected.

The self-triggering mechanism provides a mechanically enabled drug administration system which eliminates need of battery or external power source. This facilitates use of the device in remote settings, war zones and places without access to power sources.

The wearable finger-mounted drug administration device of invention is, furthermore, provided with a mechanical flow-rate controller. The mechanical flow-rate controller eliminates need for calibration and replacement of the controller unit due to wear and tear.

The wearable finger-mounted drug administration device of invention is also provided with a dual dosage control in order to prevent incorrect dosage administration, achieved by means of an external knob placed around the injection drug-pod chamber which controls the volume of the drug-pod chamber and dimensions of the drug-pod which vary with specific dosage volumes of the injectable substances.

The invention further describes a novel design of a drug-pod containing an injectable substance for use with the wearable injection device; and a drug-pod casing. The novel design of drug-pod containing the injectable substances allows administration of extremely low doses of drug is achieved using.

The wearable finger-mounted drug administration device of the invention facilitates controlled administration of injectable substances; for easy administration of vaccines; for administration or self-injection of intermittent injectable medication for allergies, hormone administration etc.; and for daily administration or self-injection of injectables for treatment of chronic diseases including diabetes, arthritis, asthma, other autoimmune disorders, cancer, chronic obstructive pulmonary disease (COPD) etc., and some viral infections such as Hepatitis C, HIV/AIDS etc.

In an embodiment, the drug administration device comprises of a wearable finger-mounted injection device with self-triggering mechanism for controlled administration of injectable substances; a novel design of a drug-pod containing an injectable substance for use with the wearable injection device; and a drug-pod casing.

Accordingly, as shown in Fig. 2, the wearable finger-mounted drug administration device (200) of the invention comprises of a needle insertion unit (201) consisting of a slot for the needle casing to slide into the device. The needle casing has a self-fitting lock to fit positively into the device and an aligning gap at the distal end for the needle to enter into the drug-pod chamber. The needle insertion unit (201) also features one or more self-retracting manual buttons along its circumference to remove the needle casing along with needle after the dosage administration. The needle insertion unit (201) is attached to the drug-pod chamber (202), which comprises of a smooth coated chamber barrel for easy functioning of the device (200) a driving mechanism and a 3-dimensional barrel profile conforming to the drug-pod pusher (203) head for complete administration of injectable substance into the body of the user.

The top view of the device is shown in Fig. 3. The drug-pod chamber has a lid (207) with an inner profile matching the chamber barrel curvature. The said lid (207) when closed, presses drug-pod (208), loaded in the drug-pod chamber (202), such that the drug-pod occupies all the available space in the barrel completely. The lid (207) rises the pressure inside the drug-pod (208), such that, an equivalent pressure is required to push the drug to the tip of the needle when the needle punctures the drug-pod (208). This mechanism helps in the priming of the device before inserting the needle into the injection site.

The device (200) is provided with a drug-pod pusher (203) that features curvature on the top end which conforms to the shape of the barrel of the drug-pod chamber. The drug-pod pusher (203) head has smooth edges along its circumference, which is in constant contact with the inner profile of the drug-pod chamber (202) and conforms to the shape of the chamber barrel such that the injectable substance is released completely from the drug-pod (208) during dosage administration. As shown in Figure 3, the drug-pod pusher (203) has a small self-locking extension (210) for locking the pusher (203) while the user is setting the dosage and loading the drug-pod (208) in the chamber. The drug-pod pusher (203) has long connecting rod (204) at the rear end which connects the pusher (203) to a driving mechanism (205) and an annular ring which is preferably made of magnetic material, at a specified region on the connecting rod (204) therefore establishing interaction with the controlled drug release mechanism (212) of the device.

The device (200) further features a self-triggering mechanism which comprises of a button (209) on the device head as shown in Figure 3, which interacts with the body of the user when pressing the device to the injection site. The design of the button (209) on the device head and the needle insertion unit (201) ensures an optimum angle for dispensing the injectable substance. The button (209) self-retracts when the device is removed from the body.

The button (209) links with the self-locking extension (210) of the drug-pod pusher which has multiple locking positions for receiving different sizes and volumes of drug-pods (208) in the drug-pod chamber (202). The self-locking mechanism (210) facilitates easy movement of the drug-pod pusher (203) during dosage setting and restricts the movement of the drug-pod pusher (203) in other direction.

The device (200) is provided with a dosage setting knob (206) on the external surface which comprises of a circular dial with a grip on the circumference such that the user can rotate the knob (206) to set the dosage easily.

The dosage setting knob (206) is joined with a dosage setting mechanism which includes a visual indicator for determining the position of the dosage setting knob (206) for a set value of drug dose and other various similar feedback elements such as visual, audio feedbacks etc., to provide a device response to various user interactions such as dosage setting, device activation, dosage administration, completion of drug administration, status of drug-pod in the chamber etc. A central gap is provided on the dosage setting knob (206) which aligns with the smooth bush or bearing mounted on the device (200).

The dosage setting mechanism comprises a drivetrain having gears (211) to transfer the dosage setting knob (206) motion to the movement of drug-pod pusher (203). The gear train system (211), preferably worm gears or pin slot mechanism, is used to transfer the knob (206) motion into perpendicular direction of motion. In a preferred embodiment, a gear mechanism, preferably spur gears, is provided to transfer the power and maintain speed ratio for the downstream or the device driving mechanisms. The device driving mechanism comprises of a rotary to linear gear mechanism, preferably rack and pinion mechanism, to translate the rotational motion of knob (206) in linear direction, a connecting frame which joins the rack with the drug-pod pusher (203) connecting rod (204) and guides to align linear rack and pinion mechanism in a specific direction. The said connecting frame consists of a guide rod with an energy storing element (205) which interacts with the connecting frame. A stopper is used for the energy storage element (205) such that it remains in contact with the said connecting frame at all times especially during working of the device (200).
The drug-pod pusher (203) includes at least two sets of guide rods (204) for a perfect linear motion and a sound creating system, preferably a ratchet mechanism, is employed for creating an audio feedback to user while setting the dosage. The audio feedback of the device (200) works as a user indicator which includes either a clicking, ticking, snapping, popping or tapping sound, each type of sound can correspond to specific device (200) status for example, a ratchet based mechanism produces sound while dosage setting, a notably different clicking sound while the device is in use and another unique snapping sound when the dosage finishes.

The said energy storage element (205) of the device (200) stores the mechanical elastic potential energy which can be used when a dosage administration is required. The said energy storage element (205) can preferably be a coil spring constrained in a region with stoppers. The energy storage element (205) aids in controlled release mechanism of the injectable substance which comprises of a damper system maintaining the speed of administration. In a preferred embodiment, the device uses a spring as an energy storage element (205) and a mutual induction and eddy currents-based damper. The mutual induction and eddy currents-based damper consists of a highly conductive material preferably copper annular ring having a thickness or a wire coil having a length, along with an annular magnetic core mounted on the drug-pod pusher connecting rod (204) and passing through the said conductive material.

Following completion of dosage administration, the empty drug-pod in the device (200) is released from the hold of the drug-pod pusher (203) by rotating the dosage setting knob (206) and removed from the drug-pod chamber (202) by using a drug-pod removal system with constitutes a second or different lid. Alternatively, the empty drug-pod (208) can be released using a drug-pod removal mechanism preferably a pusher or a button to push the empty drug-pod out of the drug-pod chamber (202).

The device (200) includes a holder with finger mounting position (410) which has insertion point for one or more fingers of the user to slide into the device holder for providing sufficient grip while using the device (200). The holder has a soft internal surface preferably cushion of foam material for greater user comfort while using the device and a shape conforming foam material to accommodate fingers of different sizes and thickness.

In an additional embodiment, the invention describes a novel design of a drug-pod containing an injectable substance for use with the wearable injection drug administration device of the invention.

The novel drug-pods (208) (Fig. 6) of the present invention, are designed to carry injectable substances which can be used with the wearable injection drug administration device (200) as described above. The drug-pod (208) can be made of soft gelatine capsule material in different colours, shapes, dimensions and volumes, which are defined by the dosage of injectable substance it carries and compatibility for use with the wearable device (200).

The shape of the drug-pod (208) ensures correct placement of the pod in the drug-pod chamber (202) and alignment with the drug-pod pusher head (203) for facilitating complete dispensing of the injectable substance.

In one preferred embodiment, as illustrated in Fig. 8 the head (601) or (602) of the drug-pod (208) is made of soft polymer material such as silicone to enable integration with the needle in the needle insertion unit (201) of the wearable device (200) and also to permit pressure driven priming. The drug-pods (208) are designed to have no wastage of injectable substance while integrating with the needle (201) in the wearable device. In another embodiment, the drug-pods are manufactured with needles at the distal end, thereby it can be readily used with the wearable administration device. The needle used with the wearable administration device can be selected from a group comprising hypodermic needle, microneedles etc, as per the requirement of the type of injection namely intramuscular, subcutaneous, intravenous and intradermal injections.

In yet another additional embodiment, the invention provides a novel drug-pod casing (500). the drug administration system (200) includes a drug-pod casing which has multiple holders (501) for drug-pods (208) of different shapes and dimensions can be placed at specific locations and a small protrusion is provided in the drug-pod holders (501) to hold the drug-pod (208) at their location. The drug-pods are removable from the casing only when pulled out by the user. This prevents accidental removal or fall of drug-pods (208) stored in the casing. The drug-pod casing also features holders for needle casings (201) along with a cap covering with needle which is placed facing downwards in the holders (502). The rear end of the needle is exposed to air but is lying with the surrounding casing such that the rear needle tip is inside the top edge of the casing thereby obstructing accidental piercing or touching of the exposed rear end of the needle by the user. When the user pushes the device (200) on the needle casing, it snap-fits with the device and comes out of the holder along with the needle cap. The needle cap can be removed before using the device. The drug-pod casing includes a holder for storing the wearable device (200) when not in use. A disposing unit can also be provided in the pod-casing for dropping used needles and empty drug-pods. A lid on the disposing unit completely separates it from the injectable substance filled drug-pods. The surface of the drug-pod casing can have an autoclavable and sterilizable coating for cleaning various units after regular intervals. An insulating outer cover can be provided for thermal cooling or maintaining the drug-pods containing the injectable substances at required temperature in the drug-pod casing.

The drug-pod casing has reminders and indicator systems for displaying scheduled visual and audio reminders to user for administering injectable substance. The indicator can further display quantity of drug-pods at various locations in the drug-pod holder. This can be achieved by placing sensors of non-contact type preferably optical sensors below the drug-pod holder and needle casing holder for detecting status at various locations on the holder as empty and occupied with drug-pods or needle casings respectively. It can also send reminder for emptying used drug-pods and used needles from the disposing unit. The drug-pod casing can have one or more digital communication units comprising wired or wireless communication modules such as GSM module, Bluetooth, Wifi etc., to connect to smartphones, mobile devices, laptops, personal computers etc., for monitoring patient medication adherence.

In an embodiment, the invention provides method for using the wearable finger-mounted drug administration device (200) by a person other than self, which include medical professional or a care-taker or a relative. The wearable injection device (200) can be finger mounted by the user for better grip during injection of vaccines and other injectable substances to infants, children, young adults and geriatric subjects with greater control and accuracy using one hand while the other hand is free to hold the subject. Specifically, for administering vaccines for children, the drug-pod casing can carry multiple numbers and different types of injectable vaccines in drug-pods (208), each drug-pod colour coded for differentiating the type of injectable vaccine it carries. The medical practitioner, doctor or nurse can remove the wearable device stored in the drug-pod casing and mount it on the finger, before proceeding to load the drug-pod containing desired vaccine for administration. The dosage setting knob (206) is used set the desired dosage of injectable substance to be delivered and the lid (207) is opened to load the drug-pod (208) in the drug-pod chamber (202). The dosage setting knob pre-sets the volume of the drug-pod chamber (202), which along with the colour and dimension of the drug-pod, functions as a dual dosage control ensuring loading of correct dosage of the vaccine.

The device provides a sound feedback to indicate rotation of the dosage setting knob (206). The lid (207) of the drug-pod chamber (202) is closed and the user snap-fits the needle to the device (200) by pushing on the needle casing stored in the drug-pod casing. The needle casing comes out of the holder along with the needle cap. The needle cap is removed before using the device. The self-triggering mechanism of the device (200) is activated when the user presses down the device to the injection site to administer the vaccine.

The compact size and novel design of the wearable injection device eliminates anxiety and discomfort that is commonly observed among infants, children and young adults during vaccination using vial and syringe administration system.

The novel design of the device head and the needle insertion unit (201) ensures an optimum angle for dispensing the vaccine and activates the button (209) on the device head by interacting with the injection site on the body. While in use, the device makes a notable clicking sound to indicate the administration of the vaccine and a different type of sound marks the completion of dosage administration. Upon withdrawal of the needle from the injection site, the button (209) retracts automatically indicating successful completion of vaccine injection. The needle cap is replaced and the used needle along with the needle casing is removed by pressing the release buttons provided in the needle insertion unit (201) and placed in the disposing unit in the drug-pod casing. The empty drug-pod is released from the holder of the drug-pod pusher (203) by rotating the dosage setting knob (206) and removed from the drug-pod chamber (202) by opening the drug-pod removal lid (207). The empty drug-pod is collected in the disposing unit. Alternatively, the empty drug-pod (208) can also be released by using a pusher or a button provided. Finally, the wearable device is unmounted to be stored in the drug-pod casing while not is use. Alternatively, the device (200) can be loaded again as described above to vaccinate one or more subjects.

In one more embodiment, the invention provides a method for administration of the drug using the self-trigger mechanism of the wearable finger-mounted drug administration device (200). The finger-mounted wearable drug administration device (200) can be used for different types of injections namely intramuscular, subcutaneous, intravenous and intradermal injections, by enabling activation of the self-triggering mechanism at various injection angles. This is achieved by using a hollow ellipsoid shaped flap (301) that partially covers the bottom area of the device and along the curvature of the device head, that comes in contact with the body while injecting. This hollow ellipsoid flap curves along the device head to establish contact with the trigger button (209) by means of small trigger rod (302) provided at the end of the flap. The ellipsoid flap can be designed either as a single flap or as multiple flap sections, such that each flap can push the trigger button (209) using trigger rod attached to the flap. The trigger button (209) is designed in such a way that all the trigger rods can come in contact with the trigger button (209). Each flap is provided with a large hanging surface area, which acts as a self-retracting button after a press. The hollow ellipsoid flap (301) can snap-fit to the device (200) outer cover.

In one more embodiment, the invention provides a method for administration of the drug using the self-trigger mechanism of the wearable finger-mounted drug administration device (200) triggered by finger or thumb. This design of the device (200) with the trigger button (209) placed on the side of the device (200) outer body is highly relevant for injection types that are not perpendicular to the injection site or angled in such a way that the trigger button (209) when placed on the device head does not interact with the body of the injection site. For example, while administering dental injections, long hypodermic needles are used to reach internal mouth surfaces and the injecting device will not come in contact with the injection site. Hence, by placing the trigger button (209) on the side of the outer body of device (200), the self-triggering mechanism can be activated by pressing the trigger button easily with user’s thumb and/or fingers. Following are the steps used in administering a dental injection using the finger-mounted injection device (200). The device (200) is mounted on the user’s finger and the injection dosage is set using the dosage setting knob (206). The drug-pod (208) containing the injectable substance is loaded in the drug-pod chamber (202) and the lid (207) of the drug-pod chamber (202) is closed. The user snap-fits dental hypodermic needle to the device (200) by pushing on the needle casing stored in the drug-pod casing. The device (200) can receive both long and short sizes of dental hypodermic needles. The dental needles are provided with a protective sleeve such that it only exposes the length of needle from the needle tip required for penetrating the injection site. This allows control over the depth of dental injection. The needle insertion unit (201) snap-fits with the device head and the finger mounted device is ready for use. The exposed portion of the needle is provided with a needle cap which is removed before using the device. The needle is penetrated at the injection site to the desired depth and the user activates the self-triggering mechanism by pressing the trigger button provided on the side of the device (200) outer body using thumb and/or fingers. The trigger button (209) retracts automatically indicating successful completion of injection. After completion of the injection, the needle is withdrawn from the injection site, and the needle cap is replaced. The needle cap is replaced and the used needle along with the needle casing is removed by pressing the release buttons provided in the needle insertion unit (201) and disposed. The empty drug-pod is released from the hold of the drug-pod pusher (203) by rotating the dosage setting knob (206) and removed from the drug-pod chamber (202) by opening the drug-pod removal lid. The empty drug-pod is collected and disposed. Finally, the wearable device is unmounted and stored in the drug-pod casing while not is use.
,CLAIMS:1. A wearable drug administration device (200) for administration of an injectable substance comprising:
a. a needle insertion unit (201) consisting of a slot for the needle casing which snap-fits with the device head and which is configured to puncture drug-pod (208);
b. a drug-pod chamber (202) connected to the needle insertion unit (201) and configured for housing a drug-pod (208);
c. a drug-pod pusher (203) is positioned opposite to the device head and is connected to at least two sets of guide rods (204) which is configured for pressing the drug-pod (208) for delivering the injectable substance contained in the drug-pod (208);
d. an energy storage element (205) interacting with the guide rods (204), which is configured for storing the mechanical elastic potential energy which can be used when a dosage administration is required;
e. a dose setting knob (206) which is used to set the desired dosage of injectable substance to be delivered;
f. a drug-pod lid (207) placed above the drug-pod chamber (202), which facilitates insertion and/or removal of the drug-pod (208) and increases pressure inside the drug-pod chamber (202) for efficient priming of the device;
g. the drug-pod (208) which is designed to contain the drug to be administered;
h. a self-trigger button (209) placed on the body of device (200), which is configured for dispensing the injectable substance;
i. a self-locking mechanism (210) which allows for easy movement of the drug-pod pusher (203) during dosage setting and is restricted motion in other direction, and
j. a drivetrain having gears (211) to convert the rotational motion of the dosage setting knob (206) motion to the linear movement of drug-pod pusher (203).
wherein, the energy storage mechanism (205) is provided with a damper system configured for maintaining the speed of administration which aids in controlled release of the injectable substance.

2. The device as claimed in Claim 1, wherein the drug-administration device (200) is provided with a drug-pod casing (500) having multiple holders (501) to hold multitude of drug-pods (208) and needle insertion units (201).

3. The device as claimed in Claim 2, wherein the multitude of drug-pods placed in drug-pod casing may contain one or more doses of same or different medication or injectable substance.

4. The device as claimed in Claim 3, wherein, the drug-pod casing is provided with reminder and indicator system.

5. The device as claimed in Claim 4, wherein the reminder and indicator system is configured for displaying visual and audio reminders to user for administering injectable substance.

6. The device as claimed in Claim 2, wherein the drug-pod casing is provided with wired or wireless digital communication units comprising communication modules for monitoring patient medication adherence.

7. The device as claimed in Claim 1, wherein the drug-pod chamber (202) has a shape complementary to the shape of the drug-pods (208).

8. The device as claimed in Claim 1, wherein the drug pods (208) may be in different colours, shapes, dimensions and volumes, which are defined by the dosage of injectable substance it carries.

9. The device as claimed in Claim 8, wherein, the drug-pods (208) are made of soft gelatine capsule material.

10. The device as claimed in 8, wherein the drug-pod (208) may be provided with a head made of soft polymer material to enable integration with the needle in the needle insertion unit (201) of the wearable device (200).

11. The device as claimed in Claim 10, wherein the soft polymer material is silicone.

12. The device as claimed in Claim 8, wherein the drug-pod (208) may be integrated with the needle insertion unit (201).

13. The device as claimed in Claim 1, wherein the device does not require an external or internal power source.

14. The device as claimed in Claim 1, wherein the damper system comprises of a spring as an energy storage element (205) and a mutual induction and eddy currents-based damper.

15. The device as claimed in Claim 1, wherein said device is finger-mounted.

16. the device as claimed in Claim 1, wherein the device can be held in hand and triggered by finger through a flap and trigger mechanism (301-302).

17. A method for priming the device as claimed in Claim 1, wherein the process comprises steps of:
a. opening the drug-pod casing (501) to remove the desired drug;
b. setting the prescribed dose using the drug setting knob (206);
c. pushing the device into a needle casing unit to clamp the needle along with the needle casing on the front part of the device;
d. taking the desired drug-pod (208) from the drug-pod case (501), and
e. inserting the drug-pod chamber (202) by opening drug-pod lid (207) and priming the device.

18. A method for administration of the drug to the user, wherein the method comprises of:
a. placing the device (200) on the user finger and removing needle casing;
b. pressing the needle side of the device (200) to the skin, whereby the needle penetrates the skin, and
c. the drug contained in drug pod gets delivered to the desired site of drug administration.