What Are the Side Effects of Vemlidy?

All medications can cause side effects. But, not all side effects are created equal. Certain medications cause more serious issues than others. And two people taking the same medication may not experience the same side effects. 

Below, we’ll focus on the side effects of one specific medication — Vemlidy (tenofovir alafenamide). Vemlidy is FDA-approved to treat hepatitis B. Some side effects of Vemlidy are mild, and may improve on their own. Others are more serious and require monitoring throughout treatment with Vemlidy.

Continue reading to learn what you should watch out for if you take Vemlidy.

What is Vemlidy?

Vemlidy is a once-daily tablet that treats hepatitis B. Vemlidy is only available as a brand-name product at this time. 

The generic name “tenofovir” may sound familiar to you. That might be because it's used with other medications to prevent human immunodeficiency virus (HIV). HIV prevention treatment is commonly referred to as PrEP (pre-exposure prophylaxis). The medications used for PrEP typically include a form of tenofovir combined with another medication. Truvada (emtricitabine/tenofovir disoproxil fumarate) and Descovy (emtricitabine/tenofovir alafenamide) are examples of common PrEP medications.

Of note, Vemlidy is sometimes used off-label to treat HIV. It needs to be taken with other HIV medications to prevent resistance. For this reason, your provider may test you for HIV before you start Vemlidy for hepatitis B treatment.

Promotion disclosure

Vemlidy

Avg retail price

$1934.37(Save 27.45%)

GoodRx discount

$1403.43

Compare all prices

Unlike other forms of tenofovir, which are most often used for HIV, Vemlidy’s only FDA-approved for hepatitis B treatment. Each tablet contains 25 mg of tenofovir alafenamide, and the typical dose is 1 tablet once a day with food.

How does Vemlidy work for hepatitis B?

The hepatitis B virus (HBV) is a small organism that infects your liver. Sometimes, your immune system can fight the virus on its own. If your immune system is able to get rid of the virus, you won’t need medication. 

But if your body can’t clear the virus, HBV can stick around and become a chronic infection. HBV can attack your liver cells and cause liver damage. Chronic HBV infections may require medications like Vemlidy. 

Vemlidy treats chronic hepatitis B infections by affecting the virus’ ability to make DNA. If HBV can’t make DNA, it can’t make copies of itself and infect more liver cells. Vemilidy can keep the amount of HBV in your body low, which can protect your liver from inflammation and lower the risk of transmitting HBV to someone else. 

Vemlidy is currently a first-choice treatment option for hepatitis B. 

What are the most common short-term side effects with Vemlidy?

Not everyone will experience the same side effects with Vemlidy. The most common side effect is a headache. In clinical trials, over 10% of people taking Vemlidy experienced a headache. Other common side effects may include:

• Abdominal pain

• Cough

• Diarrhea

• Tiredness

• Nausea and upset stomach

• Back pain

• Joint pain

Some of these side effects are similar to symptoms of hepatitis B. So, it might not be clear if what you’re feeling is from the medication, or from hepatitis B itself. And, it’s possible that some of these short-term side effects improve as your body gets used to the medication. 

Other less common short-term side effects of Vemlidy include vomiting, rash, and gas.

What can I do to manage the short-term side effects of Vemlidy?

While many early side effects of Vemlidy will get better on their own, it’s frustrating when they affect your daily life. Here are some tips that can help: 

• If you experience tiredness or a headache, you could try taking Vemlidy in the evening before you go to bed. That way, these side effects will have less of an effect on your day.

• You can sometimes take over-the-counter (OTC) pain medications like ibuprofen (Advil, Motrin) or acetaminophen (Tylenol) if you experience a headache or back pain. Always check with the healthcare provider first because these OTC products can sometimes be harmful to the liver and kidneys. 

• Always remember to take Vemlidy with food. Food helps your body absorb the medication, and it can help prevent stomach upset. 

Are there any long-term side effects of Vemlidy?

Kidney and bone problems are long-term side effects associated with tenofovir. But, Vemlidy contains a newer form of tenofovir (tenofovir alafenamide). Studies have shown that Vemlidy may not have as much of an effect on your bones and kidneys that Viread (tenofovir disoproxil fumarate) might have. Still, it’s important to monitor for these side effects.

Getting regular blood work drawn is an important part of treatment with Vemlidy. You’ll likely have kidney and liver blood tests done before starting and throughout treatment. These tests will help your healthcare provider monitor how well the medication is working. It also helps them monitor your liver and kidney health. 

People with existing kidney problems are more likely to experience kidney-related side effects while taking Vemlidy. If your kidney health worsens, your provider might switch you to another hepatitis B medication. 

Make sure you talk to your provider before starting any medication while you’re taking Vemlidy. There are other medications that can also harm your kidneys that you may want to avoid.

Your bone health, on the other hand, is not monitored regularly with labs. However, many people who take tenofovir-containing medications also take vitamin D and calcium supplements to prevent bone problems. Even with commonly used supplements, it’s still best to check with your healthcare provider before you start taking them. 

When should I contact my healthcare provider about side effects from Vemlidy?

You should contact your healthcare provider if your side effects are preventing you from taking Vemlidy every day. In most cases, you should contact your provider before you stop the medication. This is because suddenly stopping Vemlidy can cause your hepatitis B infection to flare. Depending on the side effects you’re having, your provider may want you to try a different hepatitis B medication.

It’s rare, but some people who take Vemlidy develop a liver problem where they have too much lactic acid in their blood (lactic acidosis). Symptoms can include weakness, extreme tiredness, and unusual muscle pain. It can also include trouble breathing and a fast or irregular heartbeat. If this happens to you, stop taking Vemlidy and seek medical help right away.

Why trust our experts?

Written by:

Hope Chang, PharmD, AAHIVP

Hope Chang is a freelance writer and content reviewer for GoodRx. She attended Howard University College of Pharmacy in Washington, D.C. and completed post-graduate residency training at the University of California, Davis Medical Center.

Edited by:

Amy B. Gragnolati, PharmD, BCPS

Amy Gragnolati, PharmD, BCPS, is a pharmacy editor for GoodRx. Amy currently holds her pharmacist license in Georgia and California.

Reviewed by:

Christina Aungst, PharmD

Christina Aungst, PharmD, is a pharmacy editor for GoodRx. She began writing for GoodRx Health in 2019, transitioning from freelance writer to editor in 2021.

Our editorial standards

Meet our experts