The most frequently asked questions
Here you will find a list of the most frequently asked questions. If you have any further questions, simply send us an e-mail to
What is PrEP?
HIV pre-exposure prophylaxis (in short: PrEP) is a drug with which HIV-negative persons can protect themselves effectively against HIV infection.
Does PrEP protect against all sexually transmitted infections?
PrEP only protects against HIV and not against other sexually transmitted infections.
How do I take PrEP?
In the case of On Demand PrEP take two tablets 2 to 24 hours before unprotected sex, after which one tablet daily at the same time (plus/minus 2 hours). Continue taking one tablet a day for two days after the last time you have unprotected sex.
In the case of Daily PrEP start taking the tablets 7 days before your first unprotected sex. The medication is then taken on a daily basis. If you wish to stop taking PrEP, you must continue taking the medication for a further seven days after your last unprotected sex.
Is the application the same for men and women?
On Demand PrEP is not suitable for women, since the full protective effect builds up more gradually in the vaginal tract. Therefore this method is only recommended for men. Thus only Daily PrEP is recommended for women.
What is my PrEP medication?
Emtricitabine/Tenofovirdisoproxil 200 mg/245 mg Mepha. The package contains 30 tablets. This medication is the only generic PrEP approved in Switzerland. It is gluten and lactose free.
What are the possible side effects?
As a rule, PrEP is well tolerated. Gastrointestinal disorders are the most common side effects reported, in particular when starting with the prophylaxis. Kidney damage may also occur (regular checks required) and there can be a decrease in bone density.
How effective is PrEP?
In the case of regular, daily administration (Daily PrEP) the risk of becoming infected by HIV through sex is reduced by up to 99%. If On Demand PrEP is taken correctly the risk is reduced by up to 96%. The safest prophylactic is still Daily PrEP. Complete protection is reached after 5-7 days in the case of anal sex. Complete protection is reached after about 20 days in the case of vaginal sex.
How fast is PrEP effective?
Due to better efficacy, daily intake (= continuous PrEP) is generally recommended. Full protection against anal intercourse is assumed after 5-7 days, with vaginal intercourse after about 20 days.
What should I do if I forget to take a Daily PrEP tablet?
If you forget a tablet but have not had sex: take the forgotten tablet immediately.
If you forget a tablet but have had sex: Infection is unlikely if you have been taking the tablets for the past 5-7 days. However, take a tablet as soon as you remember.
If more than 12 hours have passed before you remember to take a tablet and it is almost time for the next dose, do not take the missed dose but simply continue with the next dose as normal.
When should I not take PrEP?
PrEP is contraindicated for people with unknown or positive HIV status, for hypersensitivity to the active ingredients or one of the excipients, and for severe renal dysfunction. Also for patients requiring dialysis.
Why do I need a prescription from the doctor for my order?
PrEP is only available on prescription and must only be taken under medical supervision. Before starting with PrEP you must have a consultation with a medical specialist. During this consultation tests are carried out to check for sexually transmitted diseases, blood and kidney values are measured and your HIV status is determined. In order for us to be able to send you the medication as required, we therefore need a doctor’s prescription.
What happens with my data?
Your data are only processed by Apotheke Schaffhauserplatz AG in line with the information required for storing drug-related data in order to sell mail order medicinal drugs. We treat your data confidentially and do not pass them on to third parties.
Why do I have to confirm my identity for my order?
By confirming your identity, we ensure that no-one apart from yourself can order and receive PrEP in your name.