Pharmaceutical formulation containing opioid agonist, opioid antagonist and irritant agent
Disclosed in certain embodiments is an oral dosage form comprising: a therapeutically effective amount of an opioid analgesic; an opioid antagonist; and an irritant in an effective amount to impart an irritating sensation to an abuser upon administration of the dosage form after tampering.
1. A method of treating pain comprising administering to a patient an oral dosage form comprising: a therapeutically effective amount of an opioid analgesic; an opioid antagonist; and an irritant in an effective amount to impart an irritating sensation to an abuser upon administration of said dosage form after tampering.
2. The method of claim 1 , wherein the irritant is selected from the group consisting of capsaicin, a capsaicin analog, and mixtures thereof.
3. The method of claim 1 , wherein the irritant is a capsaicin analog selected from the group consisting of resiniferatoxin, tinyatoxin, heptanoylisobutylamide, heptanoyl guaiacylamide, isobutylamide, guaiacylamide, dihydrocapsaicin, homovanillyl octylester, nonanoyl vanillylamide, and mixtures thereof.
4. The method of claim 1 , wherein the irritant is capsaicin.
5. The method of claim 1 , wherein the irritant is vanillylamide.
6. The method of claim 1 , wherein the irritant is in a sequestered form.
7. The method of claim 1 , wherein the antagonist is in a sequestered form.
8. The method of claim 1 , wherein the antagonist and the irritant are both in sequestered forms.
9. The method of claim 1 , wherein the irritant is in an amount of about 0.00125% to about 50% by weight of the oral dosage form.
10. The method of claim 1 , wherein the irritant is in an amount of about 1 to about 7.5% by weight of the oral dosage form.
11. The method of claim 1 , wherein the irritant is in an amount of about 1 to about 5% by weight of the oral dosage form.
12. The method of claim 1 , wherein said oral dosage form comprises a pharmaceutically acceptable excipient.
13. The method of claim 12 , wherein said excipient is a sustained release excipient.
14. The method of claim 1 , wherein said oral dosage form provides an analgesic effect for at least about 12 hours after oral administration to a human patient.
15. The method of claim 1 , wherein said irritant is at least partially interdispersed with the opioid analgesic.
16. The method of claim 1 , comprising combining the opioid antagonist and said opioid analgesic prior to the administration in a ratio of opioid antagonist to opioid analgesic such that the combination is analgesically effective when administered orally, but is aversive in physically dependent human subjects, when administered at the same amount or at a higher amount than said therapeutically effective amount.
17. The method of claim 16 , wherein said ratio of opioid antagonist to opioid analgesic maintains an analgesic effect but does not increase analgesic efficacy of the opioid analgesic, relative to the same therapeutic amount of opioid analgesic when administered to human patients without said opioid antagonist.
18. The method of claim 1 , wherein the antagonist is in an amount to attenuate a side effect of said opioid analgesic selected from the group consisting of anti-analgesia, hyperalgesia, hyperexcitability, physical dependence, tolerance, and a combination of any of the foregoing.
19. The method of claim 1 , wherein the amount of antagonist released during a dosing interval enhances the analgesic potency of the opioid analgesic.
20. The method of claim 1 , wherein the amount of the opioid antagonist administered is about 100 to about 1000 fold less than the amount of the opioid analgesic administered.