Drug Interaction Report

Talk to your doctor before using dapsone together with sulfamethizole. Dapsone can cause a condition called methemoglobinemia that reduces the oxygen-carrying capacity of the blood to different organs, and combining the medication with sulfamethizole may increase the risk. Infants and patients with certain conditions such as glucose-6-phosphate dehydrogenase deficiency or anemia are more likely to develop this condition. You should seek immediate medical attention if you notice signs and symptoms such as a gray discoloration of the skin, mouth, or nail bed; nausea; headache; dizziness; lightheadedness; fatigue; shortness of breath; rapid or shallow breathing; a rapid heartbeat; anxiety; and confusion. It is important to tell your doctor about all other medications you use, including vitamins and herbs. Do not stop using any medications without first talking to your doctor.

Do not take iron supplements, multivitamins, calcium supplements, antacids, or laxatives within 2 hours before or after taking oxytetracycline. These products can make oxytetracycline less effective in treating your infection. Do not take oxytetracycline with milk or other dairy products, unless your doctor has told you to. Dairy products can make it harder for your body to absorb the medication.

Iron can bind to oxytetracycline in the gastrointestinal tract, which may prevent their absorption into the bloodstream and possibly reduce their effectiveness. To avoid or minimize the interaction, iron-containing medications and oxytetracycline should preferably be taken at least three to four hours apart in most cases. Talk to your doctor if you have any questions or concerns, or if you have trouble separating the dosing times. Your doctor may be able to prescribe alternatives that do not interact. It is important to tell your doctor about all other medications you use, including vitamins and herbs. Do not stop using any medications without first talking to your doctor.