PSSD or Post-SSRI Sexual Dysfunction really worries me. This is when you carry on experiencing the sexual side effects of an SSRI for years after stopping taking the medication.
If you take a single pill and then stop, you may feel a few side effects including sexual dysfunction, but I find it very unlikely that you will carry on experiencing this side effect for years to come, from one pill. I think the same applies if you take an SSRI daily for 3 weeks. You will likely experience the side effects for the 3 weeks, and then maybe for a couple of weeks afterwards, but I do not think that 3 weeks of medication is significant enough to leave you with sexual side effects for years or forever. The brain is very plastic and can heal remarkably well.
But then you here stories about people who have taken SSRI's for months and then stopped, but then carried on experiencing sexual dysfunction for years or permanently.
So where's the line? How long do you have to take them for before PSSD becomes a risk?