Claims
- 1. A dosage form for delivering an antiepileptic drug to a gastrointestinal tract, comprising:
a compartment containing a drug formulation layer, the drug formulation layer comprising an antiepileptic drug; a semipermeable wall surrounding the compartment, the semipermeable wall having a passageway that allows communication between the compartment and an exterior of the dosage form; an internal lamina formed on an inner surface of the semipermeable wall, the internal lamina being substantially soluble in water; wherein the internal lamina in a hydrated state forms a gelatinous layer that lubricates the semipermeable wall, thereby substantially preventing crack formation in the semipermeable wall while the dosage form is dispensing the drug.
- 2. The dosage form of claim 1, wherein the internal lamina comprises one or more water-soluble polymers.
- 3. The dosage form of claim 2, wherein the one or more water-soluble polymers are present in the internal lamina in an amount of at least 80% by weight.
- 4. The dosage form of claim 2, wherein the water-soluble polymers are selected from the group consisting of hydroxy alkylcellulose, hydroxypropyl alkylcellulose, carboxy alkylcellulose, and polyalkylene oxide.
- 5. The dosage form of claim 1, wherein the semipermeable material is selected from the group consisting of cellulose acylate, cellulose diacylate, and cellulose triacylate, and blends thereof.
- 6. The dosage form of claim 1, further comprising an expandable layer disposed in the compartment, the expandable layer assisting in delivery of the antiepileptic drug through the passageway.
- 7. The dosage form of claim 6, wherein the internal lamina forms a permeable interface between the semipermeable wall and the antiepileptic drug formulation layer.
- 8. The dosage form of claim 7, wherein the internal lamina forms a permeable interface between the semipermeable wall and the expandable layer.
- 9. The dosage form of claim 1, further comprising an external lamina formed on an external surface of the semipermeable wall.
- 10. The dosage form of claim 8, wherein the external lamina comprises an antiepileptic drug and is configured to immediately deliver the antiepileptic drug in the gastrointestinal tract.
- 11. A process for maintaining the integrity and performance of a dosage form having a semipermeable wall enclosing an antiepileptic drug formulation, comprising:
laminating an inner surface of the semipermeable wall with a lamina that is substantially soluble in water; wherein the lamina when hydrated forms a gelatinous layer that lubricates the semipermeable wall, thereby substantially preventing crack formation in the semipermeable wall as the dosage form dispenses the drug.
CROSS REFERENCES TO RELATED APPLICATIONS
[0001] This application is a continuation-in-part of U.S. application Ser. No. 10/262,153, filed Sep. 30, 2002, which is a continuation of U.S. application Ser. No. 08/440,378, filed May 12, 1995, now abandoned, which is a divisional of U.S. application Ser. No. 08/234,092, filed Apr. 28, 1994, now abandoned, the contents of which are incorporated herein by this reference.
Divisions (1)
|
Number |
Date |
Country |
Parent |
08234902 |
Apr 1994 |
US |
Child |
08440378 |
May 1995 |
US |
Continuations (1)
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Number |
Date |
Country |
Parent |
08440378 |
May 1995 |
US |
Child |
10262153 |
Sep 2002 |
US |
Continuation in Parts (1)
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Number |
Date |
Country |
Parent |
10262153 |
Sep 2002 |
US |
Child |
10817500 |
Apr 2004 |
US |