Don’t panic! If you miss a dose of PrEP, you’re still protected. This is because the medication stays in your tissues for a while.
If it’s been less than 12 hours since you usually take your PrEP, then take it as soon as you remember. Then go back to your usual schedule the next day.
If it’s been more than 12 hours since you usually take your PrEP, then just wait until the next day. No need to worry.
Don’t take a double dose to catch up. It won’t give you any more protection, but it might give you some side effects like nausea.
If you’re traveling and changing time zones, try to factor this in and stay close to your usual schedule (to keep doses 24 hours apart).