Side effects

PEP emergency medicines for exposure to HIV

Some people have side effects with PEP medicines and others have none at all. If you have any side effects, get medical advice as soon as you can.

Do not stop taking the medicines, unless advised by your doctor.

Side effects of emtricitabine / tenofovir disoproxil

These tablets can commonly cause:

  • nausea (feeling sick) and vomiting (being sick)
  • dizziness
  • a headache
  • muscle pain and weakness

The tablets can also affect how well your kidneys work, but we monitor this regularly while you take the treatment.

Side effects of raltegravir

These tablets can commonly cause:

  • nausea (feeling sick) and vomiting (being sick)
  • dizziness or a feeling of spinning
  • a headache
  • indigestion or other stomach problems
  • decreased appetite
  • problems sleeping (insomnia)
  • abnormal dreams
  • a rash
  • tiredness
  • abnormal blood test results

You can find more information about known side effects of these medicines in the leaflets supplied in the medicine packets.

If your first kidney or liver tests were abnormal, you will have repeat tests 2 weeks after starting PEP.

What to do if you have side effects

You can take simple pain relief for headaches or muscle aches.

The medicines can make you feel sick (nausea) and be sick (vomiting). If this happens, it might affect how well your treatment works (especially if you are sick soon after taking a dose).

Side effects can get better over time, but it’s important to get medical advice as soon as possible.

You can contact a GP, walk-in centre, occupational health service (if you were exposed at work) or a pharmacist for advice. You can also contact the 24-hour GP service in your area. Your local GP's answerphone message should have the details of this service.

If you are concerned about any other side effects, contact your follow-up clinic, GP or NHS 111.

If you think that you might need urgent medical help, go to your nearest emergency department (A&E). 

Contact a GP if:

  • you have a severe rash with a high temperature (fever)
  • you have muscle aches
  • you have mouth ulcers (small, painful patches or lumps inside your mouth)
  • you have the eye condition conjunctivitis (when your eyes are red and sore because of an infection or allergy)

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Contact us

Phone: 020 7188 7707

For medical students on electives abroad:

Contact the occupational health department.

In an emergency, phone 020 7848 6490 or email [email protected] 

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