What Does "Earliest Fill Date" On A Controlled Substance Prescription Mean?

In this article, our pharmacist discusses what "Earliest Fill Date" on a controlled substance prescription means and what you should do if your doctor gave you a prescription that indicates a "Earliest Fill Date".

What Does "Earliest Fill Date" On A Controlled Substance Prescription Mean?
Oct 25, 2017

Rener asked

My prescription for a controlled substance says on the hard copy: “Earliest Fill Date”: 11/2/2017.1). When can I Fill this medication?2). Should I take this prescription to my pharmacy?

Answer

Controlled Substance WritingWhen it comes to controlled substance prescriptions, the laws varies from state to state, but a writing a prescription with an  "Earliest Fill Date" is a commonly used and beneficial practice for all involved.

It is very common that prescribing practitioners write "earliest fill date" on prescriptions, as it indicates to the dispensing pharmacy the appropriate day a controlled substance prescription should be filled, or at the very least, not filled before. They will pick the appropriate date based on their prescribing history for you so you can consistently get your medication on the same day each month (depending on how many days there are in the month of course!).

This is a better practice (on most occasions) than simply sending a prescription to a pharmacy the day the prescription is due as it can help to avoid problems. If prescriptions are simply sent over to a pharmacy when they are "due", you could run into inventory issues, technological problems sending the prescription over, communication issues between the doctor and pharmacy etc... Building lead time for controlled substance prescriptions is very important and can prevent delay in dispensing your medication appropriately and on time.

Another reason why this is a commonly used practice is that it keeps everyone on the same schedule. Pharmacies typically fill prescriptions they day they receive them, but when it comes to controlled substances, the laws are very strict and it is good to have a firm date the doctor wants the prescription filled. States vary on their laws, but generally there is not much room for changes in regards to when controlled substance prescriptions can be filled on a monthly basis. Writing "Earliest Fill Date" eliminates this guesswork.


It is very important that your prescriptions are not 'post dated'. They must be dated on the day they are signed by the doctor. As mentioned above, they can say "earliest fill date" or "fill-by", but they must have an appropriate written date. It is a federal law that requires all prescriptions for controlled substances "be dated as of, and signed on, the day when issued."

In terms of when you can fill the medication, per federal regulations, prescriptions that contain instructions from the prescriber indicating a fill date cannot be filled before that the date.

Depending on your fill history, your pharmacy will be able to indicate to you when they plan on filling the prescription. If you are too early (i.e. trying to fill the prescription when you already have sufficient supply), they may hold your prescription fill date for longer. Laws vary by state in regards to how much supply you can have on hand. Please check with your pharmacy regarding the actual fill date. Even if your doctor indicates a 'earliest fill date', that date may be too soon to dispense the medication depending on the records your pharmacy has for your fill history.

You should bring your prescription to the pharmacy, as long as it is not post dated. Bringing in the prescription early will allow the pharmacy time to order the drug if necessary and work out any potential issues before your fill date.

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