Drug Interaction Report

Using calcium carbonate together with proguanil can decrease the effects of proguanil. Calcium carbonate and proguanil should be taken at least 2 to 3 hours apart. You may need a dose adjustment or special test to safely use both medications. 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.

Calcium absorption may be increased by taking it with food. However, foods high in oxalic acid (spinach or rhubarb), or phytic acid (bran and whole grains) may decrease calcium absorption. Calcium may be taken with food to increase absorption. Consider spacing calcium administration for at least 2 hours before or after consuming foods high in oxalic acid or phytic acid. Talk to your doctor if you have any questions or concerns. 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.

Food significantly enhances the absorption of atovaquone. You should take each dose of atovaquone at the same time each day with a meal or a milky drink. If you receive enteral nutrition (tube feeding), take atovaquone with your feeding. Taking it on an empty stomach may lead to inadequate blood levels and reduced effectiveness of the medication. Talk to your doctor if you have questions or have difficulty taking atovaquone with food.