There are many good pharmacies in Lima, Peru. Pharmacies are called “Farmacias” or “Boticas” in Spanish. Pharmacies like “Boticas BTL”, “InkaFarma”, and “Boticas FASA” for example, are well regarded as safe places to buy medicines and personal care items and the ones I am familiar with, there are many other good ones but I just don’t have the experience to properly talk about their services.
Besides the pharmacies mentioned above, each of the major Hospitals and Clinics will have a pharmacy on the first floor carrying the majority of the medicine being prescribed by the doctors. First, bring your prescription to the pharmacy, the pharmacist will give you a purchase bill that you take to the cashier (should be in the same first floor, maybe yards away) and then bring your receipt back to pick up your medicine.
Besides medicines, pharmacies will carry personal care items like shampoo, deodorant, toothbrush, toiletries, mouth wash, electric toothbrushes (just mentioned this because it drove me crazy trying to find a place to buy one), powder baby food, diapers, etc. Think a Walgreens or CVS in miniature. No magazines or Hallmark cards or drinks (except for Energy drinks) or food (chocolate or candy).
Some pharmacies are open at night. Not completely open but will have a small square opening on the front metal door. Just start talking through the opening and someone will come up to help you.
If you are buying condoms, ask for a brand or the expensive ones, if that is what you have in mind and want to make sure that some protection will be achieved; otherwise you will be offered the cheap rainbow brand.
Sales of fake medicines or medicines past their expiration time (re-branded to appear as new) or medicines of dubious origins are a constant problem in Lima, Peru. Most of these medicines are sold around the poorest areas of Lima and as long as you stick to any of the good pharmacies mentioned above everything should be okay. Always look at your medicine and check the expiration date anyways.
There are some medicines that you will not find in pharmacies in Lima. For example, last time I was there I woke up with a nasty sore throat. Trying to find Halls sore throat pain relievers was next to impossible and I was offered only vitamin C candy. Although you can ask for Excedrin headache pills I don’t think these are very strong. In general bring your own medicine like antihistamines if you know you are going to need them. Every time I travel to Peru I carry the following: Motrin, Excedrin, Maalox, and Nyquil Day and Night. And now even Halls.
Pharmacists can give you some pretty powerful over-the-counter medicine. Granted is better if you see a doctor and get diagnosed before taking any medicine but if you described your symptoms to the attendant he or she should be able to give you appropriate medication.
A little bit on the side, but feel free to ask you taxi driver to make a quick stop at a pharmacy if you need to buy anything before heading to your destination. If you know what you want to buy you can ask your hotel attendant to order by phone and your purchase will be delivered to your hotel. Just tip accordingly.
Be aware that many of the medicines that we know by brand name in the United States are called different or under another brand name in countries like Peru. Ask for a brand name and not the generic, if possible investigate the name using the Internet.
Some pharmacies are very good places to change your dollars too, offering better exchange rates than most banks. Just ask for the rate and decide to make your purchase in dollars or not.