Claims
- 1. An improved ruminal drug delivery device for placement in an environment of use, said device comprising:
- a semipermeable wall defining a compartment;
- a drug formulation containing a drug to be dispensed;
- a density element;
- an osmotic expandable driving member, the osmotic expandable driving member contained within the compartment;
- exit means for fluidly connecting the drug formulation with the environment of use; and
- barrier means for separating the density element from the drug formulation, the barrier means being essentially impermeable to gases.
- 2. An improved ruminal delivery device according to claim 1 wherein the barrier means is a coating on the density element.
- 3. An improved ruminal delivery device according to claim 1 wherein the barrier means comprises material selected from the group consisting of polyvinyl alcohol, polypropylene, cellulose, cellulose esters, acetyl resins, fluorocarbon polymers, polyamides, polyesters, polyolefins, nylon, and noncorrosive metals.
- 4. An improved ruminal delivery device according to claim 1 wherein the drug is ivermectin.
- 5. An improved ruminal delivery device according to claim 1 wherein the improvement further comprises venting means between the density element and the barrier means.
- 6. An improved ruminal delivery device according to claim 1 which further comprises a moveable partition layer between the drug formulation and the expandable driving member.
- 7. An improved ruminal delivery device according to claim 1 wherein the barrier means comprises an exit port screen.
- 8. An improved ruminal delivery device according to claim 1 wherein the barrier means further comprises a loading dose chamber and a loading dose.
- 9. An improved ruminal delivery device according to claim 1 wherein the barrier means is fixedly engaged with the wall.
- 10. An improved ruminal delivery device according to claim 1 wherein the barrier means further includes means for retaining the density element within said compartment.
CROSS-REFERENCE TO COPENDING APPLICATIONS
This application is a continuation-in-part of U.S. patent application Ser. No. 08/081,743, filed Jun. 23, 1993 now U.S. Pat. No. 5,431,919.
US Referenced Citations (9)
Foreign Referenced Citations (1)
Number |
Date |
Country |
WO9011856 |
Oct 1990 |
WOX |
Continuation in Parts (1)
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Number |
Date |
Country |
Parent |
81743 |
Jun 1993 |
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