What Is Descovy Used For – Plus How It Works and Side Effects

Written by Phil Rossi

NowRx Pharmacy

descovy hiv prep medication

Descovy for PrEP is a prescription medication that belongs to a class of drugs called HIV, ART combos. These medications lower the risk of contracting HIV in at risk populations. When taken correctly, Descovy is 99% effective at reduces the risk of getting HIV from sex.

This article explores how Descovy works, common side effects, and other frequently asked questions related to pre-exposure prophylaxis.

Let’s dive in!

What Is Descovy

Descovy is the brand name for the medication emtricitabine/tenofovir alafenamide. This medication lowers the risk of contracting HIV during sex. When taken as prescribed, Descovy is highly effective at preventing HIV during sex. In fact, it can lower the risk of contracting HIV through sex by up to 99%.

Gilead Sciences created Descovy, which gained FDA approval in 2019. Since then, it has become one of the most popular HIV PrEP pill options. Other options for PrEP include Truvada, which was also created by Gilead Sciences as well as its generic counterpart from Teva Pharmaceuticals.

Some estimate that more than 1 in 3 new PrEP prescriptions are for Descovy.

What Is Descovy Used For

Descovy is used for preventing HIV, especially in at-risk populations. When taken as prescribed, it is highly effective and can lower the risk of contracting HIV through sex by up to 99%. Descovy is one of several HIV PrEP (pre-exposure prophylaxis) pills which means that the pill must be taken before the person comes into contact with HIV. At the moment, Truvada or Descovy are the main options for PrEP.

According to the medication’s official website, you may benefit from taking the drug if you:

  • Don’t always use condoms
  • Had or currently have a STI
  • Have sexual partner(s) who don’t know their HIV status
  • Have sex in a geographic area or sexual network where HIV is prevalent

How does Descovy work?

Descovy works by blocking several key steps in the HIV transmission and replication process.

HIV relies on CD4 cells, a type of white blood cell, in order to spread throughout the body. The virus finds, enters, and replicates itself in these cells before killing off the host CD4 and repeating the process.

However, Descovy and other ARTs disrupt this process. These medications prevent “virus internalization” (entry), reverse transcription (replication), and the subsequent steps that lead to virus production. As a result, Descovy is able to prevent HIV contraction.

Why can’t females take Descovy?

Females can’t take Descovy because its effectiveness has not been studied in that population. Unfortunately, drug development and large-scale studies cost a significant amount of money. Gilead Sciences decided that a Descovy trial with cisgender women would require too many resources. As a result, the FDA did not approve the popular drug for people assigned female at birth.

However, Gilead says they are committed to studying the effect of PrEP on cisgender women. In addition, there are still a number of options available to females including oral tablets and injections.

How Effective Is Descovy

Descovy is highly effective at preventing HIV infection. In trials, 99.7% of people taking Descovy for PrEP stayed HIV-negative. This is slightly higher than existing options like Truvada which has a 99.4% effectiveness rate.

In addition, 100% of the people who were taking Truvada pre-trial and switched to Descovy remained HIV negative. When taken as prescribed, Descovy remains one of the most effective options for preventing HIV infection.

How long does Descovy take to work?

How long it takes Descovy to start working varies from person to person. According to the SF Aids Foundation, it can take 30 days before there is enough medication in the body. However, Gilead Sciences says “The time from initiation of DESCOVY for HIV-1 PrEP to maximal protection against HIV-1 infection is unknown”. Trials from Gilead showed that median tenofovir diphosphate concentration peaked after 6 days.

What Are The Side Effects of Descovy

Common side effects of Descovy include diarrhea, nausea, headache, fatigue, and stomach pain. Serious side effects of Descovy may include:

  • Worsening of Hepatitis B Infection
  • New or worse kidney problems
  • Lactic acidosis
  • Severe liver problems

This is not a complete list of all Descovy side effects. Your doctor will need to test and monitor your health before and throughout your treatment. Talk with your doctor if you experience new symptoms after starting treatment.

Does Descovy cause weight gain?

Descovy does cause weight gain according to some research. In a study of 1,652 eligible patients, weight and BMI increases with higher doses of emtricitabine/tenofovir alafenamide. In addition, weight increases appeared and occurred more rapidly among patients receiving higher doses (25mg) compared with lower doses. Other studies have suggested only minimal weight gain over 96 weeks of treatment.

Is Descovy Better Than Truvada

Descovy does appear to be better than Truvada on a number of characteristics related to safety and efficacy. For example, it showed a slightly higher efficacy rate compared to Truvada (99.7% vs 99.4%). Additionally, Desocvy was superior on several safety measures including markers of bone and renal (kidney) toxicity. You can learn more about each medication through Descovy vs Truvada.

How To Get Descovy For Free

Figuring out how to get Descovy for free is difficult because it will depend on your individual circumstance to some extent. For example, some health insurance plans will offer $0 copay and free testing for HIV PrEP. In addition, certain pharmacies are able to apply manufacturer coupons to lower the copay to $0 for the first few doses. Talk with your pharmacist or a trusted healthcare provider to figure out your options and if you have any questions at all, feel free to reach out to us here at NowRx Pharmacy and NowPrEP.

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