Answered by:
Stuart D. Federman, PharmD, AAHIVP
Gateway Apothecary
Saint Louis, MO

Gastrointestinal (GI) complications are a common side effect with most antiretroviral (ARV) drugs, but with many of the medications this side effect goes away within the first couple weeks of therapy.

There are some meds that are more likely to cause stomach upset, such as: Videx (didanosine), Zerit (stavudine), Retrovir (zidovudine), Viramune (nevirapine), and Kaletra (lopinavir / ritonavir). Many ARV combinations are available in the United States, so if GI problems persist there are usually other options that patients can use that may have less stomach complications.

If you are having GI symptoms regularly, you should never ignore them. These symptoms could be signs of other medical conditions that may need to be treated. There are many places in the GI tract that can cause issues with the absorption of ARVs.

A common GI complication is gastroesophageal reflux disease (GERD), where the digestive system has acid from the stomach entering the lower esophagus. To lower your risk for GERD, limit the use of the following: fatty foods, spicy foods, caffeinated beverages, citrus juice, stress, smoking, alcohol use, pregnancy, and obesity. Also limit meds such as: Lopressor (metoprolol), (Norvasc) amlodipine, Advil (ibuprofen), and aspirin.

There are several options to treat GERD, all which reduce the acid in the stomach. The complication this presents is that some HIV meds are better absorbed with a higher acid level in your stomach. Even for less serious GI illnesses such as heart burn, you should always ask your physician or pharmacist before using any over-the-counter medicine.

You should be aware of what drug combos can result in less effective treatment and how to resolve it. Antacids can lower the absorption of Tivicay (dolutegravir), Triumeq (dolutegravir / abacavir / lamivudine), Reyataz (atazanavir), and Complera (rilpivirine / tenofovir / emtricitabine), and should be given two hours before or six hours after.

H2 blockers like Zantac or ranitidine should be used as far as possible with 12 hours apart with the use of Reyataz or Complera. A proton pump inhibitor (PPI) like Prilosec, omeprazole or Nexium should not be used when you are either on Reyataz or Complera.

HIV meds can also effect certain GERD meds as well, making them less effective. Sustiva (efavirenz), Atripla (efavirenz / tenofovir / emtricitabine), and Viramune (nevirapine) should be used in caution due to their ability to increase metabolism of the PPI meds, which will cause them to be less effective.

Your gastric acid levels can decrease by eating as well. For better absorption, you should have food before taking the following medications: Reyataz, Aptivus (tipranavir), Prezista (darunavir), Stribild (elvitegravir / cobicistat / tenofovir / emtricitabine) and Norvir (ritonavir). The following meds are better absorbed when taken on an empty stomach: Crixivan (indinavir) and Videx.

For further suggestions, please talk with your pharmacist or physician.

Additional writing by Patrick Hyatt, Pharm. D candidate 2015.