You have 3 refills remaining.
You have 3 medication refills remaining.
3 Answers
I do not want to bring up more polemic over that issue, but in Northern México, we use surtir and resurtir when refering to medical prescriptions (recetas, prescripciones médicas)
The first time we use:
¿Me puede surtir esta receta por favor?.
On subsequent times, we use:
¿Me puede resurtir esta receta por favor?.
We use resurtir too when we say that we need to go to the supermarket to buy groceries:
Tengo que ir al mercado mañana para resurtir la despensa.
But, when I want to refill my soda/glass of water/cup of coffee/etc., we use rellenar, volver a servir or servir más.
Yo puedo rellenar mi vaso de refresco todas las veces que quiera cuando voy a comer a un McDonald´s.
I can refill my soda anytime a like when I go out to eat to a McDonald´s.
Me voy a volver a servir agua (en un vaso) porque aún tengo sed.
I am refilling this glass of water, because I am still thirsty.
Señorita, ¿me puede servir más café por favor?.
Waitress, please, can I have a coffee refill?
Note: I do know that resurtir is not used as defined in RAE, but that is the way it is used at least in Northern Mexico. Hope you find this useful.
To make a long story short refill is most likely to be repetición when we are speaking of refilling a medical prescription but if you want to have some fun read the post on that link.
Hi ttores: Welcome to the forum. I see you haven't taken any of the Spanish lessons yet. This website has a lot of features to help you learn Spanish. Videos, grammar articles, etc. Please read the forum rules for posting questions in the future. Good Luck.
The above link provides many answers to your question.