Alongside using condoms and the protection offered by effective treatment, PrEP is a further method of protecting yourself against HIV.

PrEP stands for pre-exposure prophylaxis. It is a preventive measure taken in oral (swallowed) form before having sex. PrEP is a medication which HIV-negative individuals who are at a higher risk of contracting HIV can take to protect themselves. The method has been scientifically verified and, if used properly, offers protection against HIV that is just as good as a condom. PrEP is available on prescription only, and should only be taken under medical supervision.

However, PrEP protects only against HIV, and not against other sexually transmitted infections such as gonorrhoea, chlamydia, syphilis or hepatitis.

How does PrEP work?

With PrEP, the active agents in the HIV drug enter the cells of the mucous membranes which come into contact with your partner's bodily fluids or mucous membranes during sex without a condom. They prevent the virus multiplying should HIV get into these cells. This prevents infection with HIV. However, to achieve this protective effect, there need to be enough of the agents in your blood and mucous membranes. The protective effect disappears when you stop taking the drug. It is usually well tolerated, but like any drug it has risks and side effects.

How is PrEP taken?

There are currently two ways of taking PrEP:

  • With long-term PrEP you start taking the drug seven days before first having sex without a condom. It is then taken daily for a defined period. It might cover a period of particularly high sexual activity, an extended holiday, or many years. When a clear decision has been made to end PrEP treatment, the drug must be taken for a further seven days before you finally stop.
  • With on-demand PrEP, you take two tablets between 24 and two hours before first having sex, followed by one tablet daily at the same time (within +/- 2 hours). After having sex for the last time, you take one tablet a day for a further two days. On-demand PrEP makes sense for weekend trips on which you might have sex, for example.

Important note: Women should not take PrEP on demand, because its full protective effect takes longer to develop in the vaginal tract. They should thus take PrEP only on a long-term basis, and its protective effect should be verified by a doctor.

Costs and availability

Basic health insurance from your normal health insurer covers your doctor's costs and the costs of the examination. Health insurers do not cover the costs of the medication itself, however. As the tablets are relatively expensive in Switzerland, a much cheaper alternative is to buy them over the internet or from a pharmacy in an EU country (they can also be ordered via a pharmacy in Switzerland). If you do not have a doctor's prescription, you are permitted to order the drug via the internet. Swissmedic permits medication to be imported both by post and in luggage, providing it is for personal use for one month at at a time. This corresponds to 30 tablets.

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