Ranitidine (Zantac)

Ranitidine (Zantac) is a histamine H2-blocker, which inhibits stomach acid production. It is used to treat stomach ulcers and acid reflux disease (heartburn). It is marketed by GlaxoSmithKline.

The commonest side-effect of ranitidine is headache.

The absorption of some protease inhibitors, notably atazanavir (Reyataz) is dependent upon the stomach acid level being high enough. Since ranitidine lowers stomach acid levels, there is a risk that patients taking atazanavir may have low levels of the protease inhibitor in the blood, putting them at risk of drug resistance and treatment failure.1 Consequently, atazanavir’s manufacturer recommends that ranitidine be taken twelve hours apart from atazanavir. A similar interaction may occur with fosamprenavir (Telzir): ranitidine should be used cautiously by patients taking this protease inhibitor.2 Patients taking tipranavir (Aptivus) should also use ranitidine with care, until the interaction between these drugs has been studied.

Ranitidine does not have significant interactions with any other antiretroviral drugs.3 However, ddI (didanosine, Videx) tablets should be taken at least two hours after ranitidine, as both drugs lower stomach acid levels.4

Despite one study suggesting that ranitidine could enhance the activity of natural killer cells in people with HIV, a larger, randomised, double-blind study showed that ranitidine had no impact on CD4 cell counts or viral load during early HIV infection.5 6


  1. Farthing C et al. Coadministration of atazanavir with proton-pump inhibitors and H2-blockers. Seventh International Congress on Drug Therapy in HIV Infection, Glasgow, abstract P289, 2004
  2. Ford SL et al. Effect of antacids and ranitidine on the single-dose pharmacokinetics of fosamprenavir. Antimicrob Agents Chemother 49: 467-469, 2005
  3. Fletcher CV et al. The effect of cimetidine and ranitidine administration with zidovudine. Pharmacotherapy 15: 701-708, 1995
  4. Knupp CA et al. Pharmacokinetic-interaction study of didanosine and ranitidine in patients seropositive for human immunodeficiency virus. Antimicrob Agents Chemother 36: 2075-2079, 1992
  5. Nielson HJ et al. Ranitidine improves certain cellular immune responses in asymptomatic HIV-infected individuals. J Acquir Immune Defic Syndr 4: 577-584, 1991
  6. Bartlett JA et al. A placebo-controlled trial of ranitidine in patients with early human immunodeficiency virus infection. J Infect Dis 177: 231-234, 1998

Community Consensus Statement on Access to HIV Treatment and its Use for Prevention

Together, we can make it happen

We can end HIV soon if people have equal access to HIV drugs as treatment and as PrEP, and have free choice over whether to take them.

Launched today, the Community Consensus Statement is a basic set of principles aimed at making sure that happens.

The Community Consensus Statement is a joint initiative of AVAC, EATG, MSMGF, GNP+, HIV i-Base, the International HIV/AIDS Alliance, ITPC and NAM/aidsmap

This content was checked for accuracy at the time it was written. It may have been superseded by more recent developments. NAM recommends checking whether this is the most current information when making decisions that may affect your health.

NAM’s information is intended to support, rather than replace, consultation with a healthcare professional. Talk to your doctor or another member of your healthcare team for advice tailored to your situation.