from POP airport to lifestyle i suggest taking the main road through the city, it's called avenida manolo tavarez justo (don't take the malecon). as soon as you pass jose luis supermarket and public hospital (both will be on your left) there is farmacia cristal on your right. parking in front of it can be challenging (not much room) and it's bound to be busy but it's a good place.
a bit further down the road, also on your right, there will gas station (sunix, i think?). there is another pharmacy there, farmacia apolinar. also good. even further down the same road, in front in UTESA university there is farmacia las flores. convenient location but i do not recommend it for purchase of medicine.
i don't think there is a pharmacy in cofresi, the closest one would be a short drive away, in costambar, just enter past the gate and it will be in a third building to your left, next to a bar and a small ferreteria.
there is a doctor's office inside lifestyle so it's possible they may have some medicine and there is a good chance that they can order a delivery for you from a pharmacy in the city but expect to pay extra.