Geminigirl is right. If you are rx'd 120 hydrocodone pills a month, you are alotted 120/30 = 4 pills per day. Sometimes the written rx can suggest more but typically the pills are to be divided out evenly over a 30 day period.
Hydrocodone which is brand named vicodin, norco, lortab, etc. is a CIII prescription, which can have a set number of refills before requiring a new written script from your doctor. If your bottle says 0 refills, you need to acquire a new written script from your doctor. I believe your doctor can fax the written script to the pharmacy versus you having to hand deliver the script to them. The latter is a requirement for CII medications.
How many days before the 30 day mark that you can get your refill is highly dependant upon your insurance company and pharmacist. A pharmacist can override what the insurance company dictates...for example, if your insurance company allows you to refill 3 days early, the pharmacist can wait to refill it until 1 day or 0 days prior to the 30 day mark (but not the other way around, they can't fill earlier than the insurance company allows)...hence it is good to have a great pharmacist working with you.
femmy
You can refill at 30 days, if it can be refilled, some of the pains meds can not be refilled, you might have to have a new prescription every month
I would check if I were you
If you were to take 4 a day (the max dose taking every 6 hours), your script for 120 tablets would be a 30 day supply. Some pharmacies will allow you to get a refill a day (some rarely will do two days) ahead of that 30 day period. Legally, they don't have to refill it until that 30 day period, even if your insurance would cover the refill a couple of days sooner.