Written with people moving from Turkey in mind. The Portuguese rules still apply more broadly.
Finding a Night Pharmacy
Standard pharmacies close around 19:00 or 20:00. If you need urgent medication at night, you must find a "Farmácia de Serviço". Every pharmacy displays a list of the nearest open ones on their door.
You can also check the farmaciasdeservico.net website. Note that buying non-urgent items (like shampoo) at 3 AM involves a surcharge; stick to emergencies.