Omeprazole magnesium

The main ingredient of this product is omeprazole magnesium.

1. This product may affect the absorption of other drugs due to its effect on gastric pH. Therefore, the absorption of ketoconazole and itraconazole will decrease when treated with omeprazole or other acid inhibitors or antacids. 2. This product is metabolized by CYP2C19 enzyme in the liver, so it will increase the plasma concentration of other drugs metabolized by this enzyme, such as diazepam, phenytoin, and warfarin (R-warfarin, low activity). Patients who are receiving phenytoin, warfarin or other vitamin K-antagonists should be monitored when starting or stopping omeprazole. 3. This product (40 mg per day) increases the Cmax and AUC of voriconazole (CYP2C19 substrate) by 15% and 41%, respectively. Voriconazole increases the AUCt of omeprazole by 280%. When used in combination and long-term treatment, the dose of omeprazole should be adjusted for patients with severe liver damage. 4. When this product is used in combination with clarithromycin or erythromycin, the blood concentration of omeprazole will increase. However, there is no interaction when used in combination with metronidazole or amoxicillin. 5. The combination of this product with drugs that inhibit CYP2C19 or CYP3A4 enzymes (HIV protease inhibitors, ketoconazole, itraconazole) may increase the plasma concentration of omeprazole. 6. Studies have shown that daily oral administration of 20-40 mg of this product does not affect other related CYP isoenzymes, and has no metabolic interaction with the following enzyme substrates, CYPIA2 (caffeine, phenacetin, theophylline), CYP2C9 (S-warfarin, piroxicam, diclofenac and naproxen), CYP2D6 (metoprolol, propranolol), CYP2E1 (ethanol) and CYP3A (cyclosporine, lidocaine, quinidine, estradiol, erythromycin, budesonide). 7. Proton pump inhibitors including omeprazole should not be used in combination with atazanavir. The co-administration of omeprazole (40 mg, once daily) with atazanavir 300 mg/ritonavir 100 mg reduces the exposure of atazanavir in healthy subjects (AUC, Cmax and Cmin are reduced by approximately 75%). Increasing the atazanavir dose to 400 mg does not compensate for the effect of omeprazole on atazanavir exposure. 8. The co-administration of omeprazole and tacrolimus increases the serum concentration of the latter. It is recommended to monitor the plasma concentration of tacrolimus when co-administration and discontinuation of omeprazole.