Bupropion as a modulator of drug activity
Dosage forms, drug delivery systems, and methods related to sustained release of dextromethorphan or improved therapeutic effects are disclosed. Typically, bupropion or a related compound is orally administered to a human being to be treated with, or being treated with, dextromethorphan.
1. A method of increasing dextromethorphan plasma levels in a human being, comprising orally administering, once a day or twice a day, a dosage form comprising bupropion and dextromethorphan to the human being, wherein the human being is an extensive metabolizer of dextromethorphan in need of treatment with dextromethorphan, wherein the dosage form contains about 75 mg to about 150 mg of the bupropion and about 45 mg of the dextromethorphan and bupropion and dextromethorphan are the only therapeutically active agents to be administered, wherein the dosage form is orally administered for at least eight consecutive days, and wherein on the eighth day that the dosage form is orally administered, the human being has a C min of dextromethorphan that is at least about 40 ng/mL.
2. The method of claim 1 , wherein the dosage form contains about 45 mg of the dextromethorphan and about 100 mg to about 140 mg of the bupropion.
3. The method of claim 1 , wherein on the eighth day that the dosage form is orally administered, the human being has a C min of dextromethorphan that is at least about 15 times the C min that would be achieved by orally administering the same amount of the dextromethorphan without bupropion for eight consecutive days.
4. The method of claim 1 , wherein on the eighth day that the dosage form is orally administered, the human being has an AUC 0-12 of dextromethorphan that is at least about 700 ng·hr/mL.
5. The method of claim 1 , wherein on the eighth day that the dosage form is orally administered, the human being has an AUC 0-12 of dextromethorphan that is about 750 ng·hr/mL.
6. The method of claim 1 , wherein on the eighth day that the dosage form is orally administered, the human being has a C max of dextromethorphan that is at least about 70 ng/mL.
7. A method of increasing dextromethorphan plasma levels in a human being, comprising orally administering, once a day or twice a day, a dosage form comprising bupropion and dextromethorphan to the human being, wherein the human being is an extensive metabolizer of dextromethorphan in need of treatment with dextromethorphan, wherein the dosage form contains about 75 mg to about 150 mg of the bupropion and about 45 mg of the dextromethorphan and bupropion and dextromethorphan are the only therapeutically active agents to be administered, wherein the dosage form is orally administered for at least eight consecutive days, and wherein on the eighth day that the dosage form is orally administered, the human being has a C min of dextromethorphan that is about 45 ng/mL.
8. The method of claim 7 , wherein on the eighth day that the dosage form is orally administered, the human being has a C min of dextromethorphan that is at least about 15 times the C min that would be achieved by orally administering the same amount of the dextromethorphan without bupropion for eight consecutive days.
9. The method of claim 7 , wherein the bupropion and the dextromethorphan are in separate domains, layers, or phases within the dosage form.
10. The method of claim 9 , wherein the domains, the layers, or the phases containing the bupropion provide sustained release of bupropion and the domains, the layers, or the phases containing the dextromethorphan provide immediate release of dextromethorphan.
11. The method of claim 7 , wherein the human being is at risk of experiencing an adverse event as a result of being treated with dextromethorphan.
12. The method of claim 7 , wherein the human being is at risk of experiencing an adverse event as a result of being treated with bupropion.
13. The method of claim 7 , wherein the dosage form is orally administered for at least 30 consecutive days.
14. The method of claim 7 , wherein on the eighth day that the dosage form is orally administered, the human being is converted to a poor metabolizer of dextromethorphan.
15. The method of claim 7 , wherein the human being is at least 18 years of age.
16. A method of increasing dextromethorphan plasma levels in a human being, comprising orally administering, once a day or twice a day, a dosage form comprising bupropion and dextromethorphan to the human being, wherein the human being is an extensive metabolizer of dextromethorphan in need of treatment with dextromethorphan, wherein the dosage form contains about 75 mg to about 150 mg of the bupropion and about 45 mg of the dextromethorphan and bupropion and dextromethorphan are the only therapeutically active agents to be administered, wherein the dosage form is orally administered for at least eight consecutive days, and wherein on the eighth day that the dosage form is orally administered, the human being has a C min of dextromethorphan that is about 40 ng/mL to 119.3 ng/mL.
17. The method of claim 16 , wherein the dosage form contains about 45 mg of the dextromethorphan and about 100 mg to about 140 mg of the bupropion.
18. The method of claim 16 , wherein on the eighth day that the dosage form is orally administered, the human being has a C min of dextromethorphan that is at least about 15 times the C min that would be achieved by orally administering the same amount of the dextromethorphan without bupropion for eight consecutive days.
19. The method of claim 16 , wherein the dosage form provides sustained release of bupropion and immediate release of dextromethorphan.
20. The method of claim 16 , wherein the dextromethorphan or the bupropion is deuterium-modified.
21. The method of claim 1 , wherein the human being is at risk of experiencing an adverse event as a result of being treated with bupropion.
22. The method of claim 16 , wherein the human being is at risk of experiencing an adverse event as a result of being treated with bupropion.