Self-driven hypodermic injector
First Claim
1. A self-driven hypodermic injector for injecting an injectable pharmaceutical preparation into a patient according to a controlled dosage regimen comprising(a) a hollow closed rigid body;
- (b) a water imbibing member mounted within the body that divides the lumen of the body into a first compartment adapted to hold the pharmaceutical preparation and a second compartment adapted to hold an aqueous liquid, the member comprising;
(i) a rigid semipermeable wall that faces the second compartment;
(ii) an expandable impermeable wall that faces the first compartment; and
(iii) a water imbibing composition contained between the rigid semipermeable wall and the expandable impermeable wall; and
(c) a conduit that extends through the wall of the body, one end of which opens into the first compartment and the other end of which is adapted to pierce the skin of the patient.
1 Assignment
0 Petitions
Accused Products
Abstract
A self-driven hypodermic injector that injects an injectable pharmaceutical composition at a constant baseline rate and may be manipulated to supplement the baseline rate with one or more pulses of the composition. The injector consists of a tubular housing with one fixed basal end wall that carries a hollow small gauge needle and one axially moveable end wall; an axially slideable water imbibing assembly mounted transversely in the housing lumen that divides the lumen into a pharmaceutical composition-containing compartment contiguous to the basal end wall and a water-containing compartment. In operation the subassembly imbibes water from the water-containing compartment and expands into the pharmaceutical-containing compartment to displace the pharmaceutical therefrom at the baseline rate. Pulses are effected by depressing the axially moveable end wall which in turn slides the subassembly toward the fixed end wall thereby exerting pressure on the pharmaceutical composition and increasing the injection rate.
215 Citations
16 Claims
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1. A self-driven hypodermic injector for injecting an injectable pharmaceutical preparation into a patient according to a controlled dosage regimen comprising
(a) a hollow closed rigid body; -
(b) a water imbibing member mounted within the body that divides the lumen of the body into a first compartment adapted to hold the pharmaceutical preparation and a second compartment adapted to hold an aqueous liquid, the member comprising; (i) a rigid semipermeable wall that faces the second compartment; (ii) an expandable impermeable wall that faces the first compartment; and (iii) a water imbibing composition contained between the rigid semipermeable wall and the expandable impermeable wall; and (c) a conduit that extends through the wall of the body, one end of which opens into the first compartment and the other end of which is adapted to pierce the skin of the patient. - View Dependent Claims (2, 3, 15, 16)
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4. A self-driven hypodermic injector for injecting an injectable pharmaceutical preparation into a patient according to a controlled dosage regimen comprising:
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(a) a rigid tubular housing have a pair of end walls that close the ends of the housing, one of the end walls providing a basal surface that is adapted to be placed against the skin of the patient; (b) a water imbibing member mounted transversely within the housing that divides the lumen of the housing into a first compartment that contains the pharmaceutical preparation and is contiguous to the housing end wall that provides said basal surface and a second compartment that contains water, the water imbibing member comprising (i) a rigid semipermeable wall that faces the second compartment; (ii) an expandable impermeable wall that faces the first compartment; and (iii) a water imbibing composition contained between the semipermeable wall and the impermeable wall; and (c) a hollow needle that extends from the first compartment through the housing end wall that provides the basal surface, one end of the needle opening into the first compartment and the other end of the needle being adapted to pierce the skin of the patient when the basal surface is placed against the skin of the patient. - View Dependent Claims (5, 6, 7, 8, 9, 10, 11, 12, 13, 14)
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Specification