Healthcare providers can treat HIV using antiretroviral therapy. A person may need to take several tablets a day or a single pill that contains multiple drugs.

In this article, we look at the benefits of single-tablet regimens (STRs). We also provide a list of drugs that doctors commonly prescribe in STRs.

What is an STR for HIV?

Phamracist holding prescription bottle of pills medication.
Single tablet regimens involve taking one daily pill to treat HIV.

Healthcare providers treat HIV with antiretroviral therapy, which involves a combination of drugs.

A person receiving HIV treatment usually takes two or more tablets every day. Each drug attacks the virus differently, and the combination is key.

A person following an STR takes a daily pill that contains a combination of two or more antiretroviral drugs.

The U.S. Food and Drug Administration (FDA) have approved over 30 drugs to treat HIV, and each works differently to prevent the virus from multiplying in the blood.

Benefits of an STR

Some HIV regimens require people to take multiple pills per day. This may mean taking different tablets at different times, either with or without food.

An STR reduces this number of pills to one.

Taking a single pill each day, compared with two or more, can make it easier for a person to follow their treatment plan, making the antiretroviral therapy more effective.

Having more effective treatment and a streamlined medication routine and can improve a person’s quality of life.

Single-tablet drug list and information

The list below provides details about medications commonly included in STRs. Each combination of drugs comes in a single daily pill.

A doctor will perform a blood test to check for the hepatitis B virus before prescribing HIV medication. Many of these drugs treat hepatitis B as well as HIV, so if a person stops taking one of these drugs, their hepatitis B may also get worse.

A healthcare provider can describe each drug in more detail and discuss possible side effects.

Some HIV drugs interact with other medications. Anyone about to start an STR should tell their healthcare provider if they are taking any prescribed or over-the-counter medicines, herbal remedies, or supplements.

STRs vs. other regimens

All HIV regimens include a combination of drugs that fight HIV in different ways. They fall into the following categories:

  • non-nucleoside reverse transcriptase inhibitors, or NNRTIs
  • nucleoside reverse transcriptase inhibitors, or NRTIs
  • integrase strand transfer inhibitors, or INSTIs
  • protease inhibitors, or PIs
  • entry inhibitors
  • CCR5 antagonists

Research indicates that people taking single daily HIV pills, rather than two or more tablets per day, are more likely to keep to the regimen at least 95 percent of the time.

This adherence is important because taking medication less often than 95 percent of the time can prevent the antiretroviral drugs from effectively suppressing HIV. It can also result in the virus developing resistance to the drugs.

People may experience more side effects from following STRs, compared to other regimens, because of the combination of drugs in a single tablet. This can also make it harder to determine which drug is causing the adverse effects.

Also, STRs contain fixed doses of the drugs, so a healthcare provider cannot adjust dosages. This makes STRs less suitable for people with existing medical conditions, such as kidney or liver problems.

Single vs. multiple pills

Man holding glass of water and pill taking medication.
A single tablet regimen may be easier to maintain than treatments involving multiple pills.

Recent evidence suggests that single pills may be more effective than combined pills. However, the research is mixed.

A 2018 study carried out by the Veterans Affairs Medical Center compared the effects of STRs to multi-tablet regimens in people starting antiretroviral therapy for the first time.

The researchers measured HIV suppression after both groups had been taking the drugs for a year. They defined HIV suppression as having a viral load of fewer than 400 copies per milliliter.

The authors reported that 84.4 percent of participants using an STR had suppressed levels of HIV, compared with 77.6 percent of those using a multi-tablet regimen.

The researchers are unsure why the STRs had better results, as both groups followed their regiments with similar regularity. However, both regimens contained different combinations of drugs, which could have affected the results.

Another study found that people are simply more likely follow a treatment plan if it involves fewer pills. There was no evidence that an STR would suppress HIV better than a two-tablet daily regimen.

Identifying whether STRs are more effective and how they achieve different results from multi-tablet regimens will require further research.


Following an STR for HIV involves taking a daily pill that contains a combination of antiretroviral medications.

In general, people find it easier to take one tablet a day, rather than multiple tablets, so STRs can help people follow their treatment plans consistently, which is one of the most important factors for staying healthy with HIV.

When deciding upon the best HIV treatment regimen, a person and their healthcare team should consider:

  • possible side effects
  • any other current medications
  • existing medical conditions
  • whether a person has experienced prior resistance to HIV drugs
  • how many pills a person will need to take each day

Discuss the options with healthcare providers, who will help identify the best course of treatment.