| Oral agent | Decreases blood glucose level | Increases blood glucose level |
|---|---|---|
| Sulfonylureas | Clofibrate (Atromid-S) | Intestinal adsorbents (charcoal) |
| Gemfibrozil (Lopid) | Cholestyramine (Questran) | |
| Histamine H2 receptor blockers | Rifampin (Rifadin, Rimactane) | |
| Probenecid (Benemid) | ||
| Salicylates | ||
| Sulfonamides | ||
| Metformin (Glucophage) | Cimetidine (Tagamet) | None known |
| Cationic drugs* | ||
| Furosemide (Lasix) | ||
| Nifedipine (Adalat, Procardia) | ||
| Acarbose (Precose) | None known | Digestive enzymes |
| Intestinal adsorbents (charcoal) | ||
| Troglitazone (Rezulin)† | None known | Cholestyramine |