The earliest you can get your gabapentin refilled is dependent on a number of factors.
Ultimately when your pharmacy says you can refill your Rx, that is when you can refill it.
I would definitely contact your pharmacy to see when you can get the refill. Personally, I could never say what day your pharmacy will tell you you can get the gabapentin.
At one time, many years ago, a thirty-day prescription could be refilled during the last 7 days of the prescription. So typically the rule of thumb used to be once 75% of the prescription was consumed/taken, then the Rx could be refilled. Things aren't this relaxed and haven't been for a good 10 years or so, as far as I know.
Another factor is your insurance. It depends on whenever your insurance will allow you to fill it. HMO's, Health Reimbursement Arraingments (HRAs), and PPOs all are the name of the game now. Are these entities typically good for the little guy? No, not usually but these are the entities we have to use if we are a working person. We get what we get.
The thing about Gabapentin is that it is many times treated like a controlled substance. Gabapentin has a similar abuse potential as Tramadol. Many pharmacies are now getting very strict on when they will allow gabapentin to be refilled. Most of the main chain pharmacies, like CVS Health, Walgreens, Rite Aid, etc, will make you wait until just a couple of days before the 30th day on a thirty-day prescription. In your case, you are getting a refill on a 90-day prescription. These pharmacies may make you wait right until a day or two before your Rx would be due, such as day 88 or day 89 after you filled the Rx.
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