The side effects of PrEP

What are the side effects of PrEP? Learn the possible symptoms of the oral and injectable forms, start-up symptoms, how to manage them, and when to see your provider.

Does PrEP have side effects

PrEP is a very safe medicine that most people use without any problem, but there are side effects worth knowing, and most are mild and manageable.

An overview of the side effects

• most are mild and usually go away as the body adjusts
• serious side effects are very rare
• they differ slightly between oral and injectable PrEP

Knowing helps you feel at ease

Understanding side effects in advance helps you avoid worry and use PrEP with confidence. Read all about PrEP at what is PrEP.

Side effects of oral PrEP

Oral PrEP is the most widely used form, and most side effects happen in the early period of use.

Common symptoms

• nausea
• headache
• tiredness
• diarrhoea or an upset stomach

Usually mild and self-resolving

These symptoms are usually mild and gradually go away on their own within the first few weeks, as the body gets used to the medicine, so most people continue PrEP comfortably.

Everyone is different

Not everyone gets side effects — many people use PrEP without feeling anything at all, while some have mild symptoms at first. How people respond to the medicine varies from person to person.

Start-up syndrome

The early symptoms of PrEP are sometimes called start-up syndrome, and they are normal.

What happens at first

In the first few weeks, the body is adjusting to the medicine, so there may be the mild symptoms mentioned above. These do not mean the medicine is harmful — they are a temporary response.

How to cope

• taking the pill with food may help reduce nausea
• drink enough water and rest
• if symptoms do not improve after several weeks, talk to your provider.

Effects on the kidneys and bones

Beyond the early symptoms, some oral PrEP regimens can have a small effect on the kidneys and bones, which is monitored.

Effect on the kidneys

Some PrEP regimens can have a small effect on kidney function in certain people, so providers usually check kidney function from time to time. This effect usually returns to normal after stopping.

Effect on bone density

There can also be a small effect on bone density, which is generally mild and reversible. Some newer regimens are designed to have less impact on the kidneys and bones, and monitoring helps you use PrEP safely.

Who should take extra care

People who already have kidney problems or a risk to their bones should tell their provider before starting PrEP, so a suitable regimen can be chosen and monitoring planned to fit their health.

Side effects of injectable PrEP

Injectable PrEP has side effects that differ a little from the pill, especially at the injection site.

Injection-site reactions

The most common side effect of injectable PrEP is an injection-site reaction, such as soreness, swelling, redness, or a small firm lump, which is usually mild and settles on its own.

Differs by type

• Cabotegravir, injected every 2 months, often causes soreness at the site
• Lenacapavir, injected twice a year, may cause a nodule or lump under the skin at the site

In studies, only a small proportion of users stopped because of site reactions, showing it is generally well tolerated.

Caring for the injection site

If the injection site is sore or swollen, a cold compress and avoiding pressure on the area help it feel better. It usually improves within a few days, and if it does not, tell your provider.

Rare effects and warning signs

Serious side effects from PrEP are very rare, but it helps to know the warning signs.

Signs to see your provider

• allergic reactions, such as a severe rash, swelling of the face or throat, or difficulty breathing
• severe physical symptoms or ones that do not go away
• symptoms that worry you or greatly disrupt daily life

Stay calm and ask

Serious symptoms are very rare, but if they happen, see a provider or go to a health service right away. Knowing these signs helps you use PrEP safely and with confidence.

Managing side effects

If you have mild side effects, there are ways to make them easier to handle.

Tips for managing

• take the pill with food to reduce nausea and stomach upset
• take it at the same time each day to help the body adjust
• rest and drink enough water in the early period
• apply a cold compress to the injection site if it is sore or swollen

Be patient at first

Early symptoms usually pass on their own, and getting through this period and asking your provider when needed helps you stay on PrEP.

Talk with your provider

Telling your provider about your symptoms helps you get the right advice, and sometimes adjusting the timing or changing the regimen helps a lot. Open communication makes using PrEP go more smoothly.

Health monitoring on PrEP

Using PrEP comes with regular health monitoring, which keeps it safe and effective.

What is usually monitored

• HIV testing at regular appointments to confirm your status
• kidney function for people on some oral PrEP regimens
• testing for other STIs as appropriate

Why monitoring matters

Monitoring lets your provider look after your health continuously and adjust your care if needed, so keeping your appointments is an important part of using PrEP safely.

Monitoring is routine

Monitoring while on PrEP is routine and not complicated, usually done at the same time as picking up your medicine, so it is not an extra burden and gives you confidence that you are using PrEP safely.

Side effects should not stop you

Many people worry about side effects and hesitate to use PrEP, but for most people, side effects should not be a barrier.

See the whole picture

Most side effects are mild and temporary, while the benefit of PrEP in preventing HIV is very high. Weighing the two leads many people to stay on PrEP.

Do not stop on your own

If you have side effects that bother you, talk to your provider first rather than stopping on your own, because stopping partway lowers your protection. A provider may be able to adjust the regimen or give advice. Read more about PrEP at what is PrEP.

When to see your provider

Knowing when to talk to your provider helps you use PrEP with peace of mind.

Talk to them when

• early symptoms do not improve after several weeks
• you have severe or worrying symptoms
• you have questions about your medicine, regimen, or monitoring

Where to ask

The provider at the clinic or hospital where you get PrEP can help answer questions and look after you. See services and how to get PrEP at where to get PrEP and how much it costs.

In summary

PrEP is a safe medicine for most people. Most side effects are mild and usually go away on their own early on. Oral PrEP may cause nausea, headache, or tiredness at first, and a small monitored effect on the kidneys and bones, while the injectable often causes injection-site reactions.

Serious side effects are very rare and should not make most people hesitate to use PrEP. The key is not to stop on your own and to talk to your provider about any concerns, along with keeping up with monitoring appointments.

If you want to start PrEP or talk about side effects, find and book a clinic at Love2Test.