Facts About Stribild, the HIV "Quad Pill"

Important Drug Prescribing Information

Photo courtesy Gilead Sciences

Stribild (also known popularly as the Quad pill) is single-tablet, fixed dose combination drug comprised of four antiretroviral agents used in the treatment of HIV:

Stribild was approved by the U.S. Food and Drug Administration (FDA) in August, 2012 for use in adults 18 and over who are starting antiretrovirals for the first time, or for those on HIV therapy who have fully suppressed (undetectable) viral loads.

The safety and efficacy of Stribild were evaluated in 1,408 previously untreated adult patients in two double-blind clinical trials, which determined that Stribild was as effective and well tolerated as Atripla, another fixed dosed domination drug comprised of tenofovir, emtricitabine and efavirenz.

In 2016, a newer formulation of the drug called Genvoya was licensed by the FDA, replacing tenofovir with a new version of the drug called tenofovir alafenamide (TAF), which is known to have fewer side effects and lower drug dosage.


Stribild is a green, oblong, film-coated tablet, comprised of 150mg of elvitegravir, 150mg of cobicistat, 200mg of emtricitabine and 300mg of tenofovir. It is embossed with "GSI" on one side and with a "1" contained in a square on the other.


One tablet daily taken with food. Stribild should not be taken with any other antiretroviral drug used to treat HIV

Drug side effects:

A number of drug side effects have been noted in patients taking Stribild. The most common adverse events, reported in 7% or more patients, were:

  • Nausea
  • Diarrhea
  • Headache
  • Abnormal dreams

Drug Interactions or Incompatibility:

Stribild should not be taken with the following drugs or supplements:

  • Anti-migraine medications: Cafergot, Migergot, Ergostat, Medihaler Ergotamine, Wigraine, Wigrettes, Ergotrate, Methergine, DHE 45
  • Anti-psychotic medication: Orap
  • Cholesterol-lowering statin medications: Zocor, Simcor, Vytorin, Mevacor, Advicor, Altoprev, Mevacor
  • Hepatitis B medication: Hepsera, Preveon
  • Prokinetic agents: Propulsid, Propulsid Quicksolv
  • Prostate medications: Uroxatral
  • Pulmonary hypertension medications: Revatio
  • Rifampin-based anti-tuberculosis medications: Mycobutin, Rifater, Rifamate, Rimactane, Rifadin, Priftin
  • Sedatives: Versed, Halcion
  • St. John's Wort


Stribild may be problematic for people with a history of kidney problems. Please advise your doctor is you have any such issues before taking Stribild. Kidney function should be routinely tested in patients on Stribild. Discontinue treatment in patients with an estimated creatinine clearance below 50mL /minute. Nephrotoxic drugs should never be coadministered with Stribild.

Two of the active ingredients in Stribild (tenofovir, emtricitabine) are also active against hepatitis B (HBV) infection. If you have HBV and stop taking Stribild, you will need to monitor your liver enzymes for several months as stopping can sometimes cause HBV to flare up.

As is the case with all first-line combination antiretroviral regimens, the NRTIs in Stribild are associated with a small risk of lactic acidosis, as well as liver problems. If you are experiencing shortness of breath; nausea and vomiting; pain or unexpected stomach discomfort; lethargy and fatigue; weakness in the arms and legs; or the yellowing of the skin and/or eyes, call your doctor immediately. Lactic acidosis, in particular, can be potentially fatal if left untreated.


U.S. Food and Drug Administration. "FDA approves new combination pill for HIV treatment for some patients." Silver Spring, Maryland; press release issued on August 27, 2012.

Wohl, D.; Cohen, C.; Gallant, J.; et al. "Elvitegravir/cobicistat/emtricitabine/tenofovir DF (STB) has durable efficacy and differentiated long-term safety and tolerability versus efavirenz/emtricitabine/tenofovir DF (ATR) at week 144 in treatment-naive HIV patients." 53rd Interscience Conference on Antimicrobial Agents and Chemotherapy (ICAAC). Denver, Colorado, September 11, 1013; abstract H-672a.

Shalit, P.;  Gallant, J.; Mills, A.; et al. "Long-term tolerability of elvitegravir/cobicistat/emtricitabine/tenofovir DF compared to efavirenz/emtricitabine/tenofovir DF or ritonavir-boosted atazanavir plus emtricitabine/tenofovir DF in treatment-naive HIV-1 infected subjects." 53rd Interscience Conference on Antimicrobial Agents and Chemotherapy (ICAAC). Denver, Colorado; September 11, 2013; abstract H-671.