A paper prescription for a common, non-controlled medication is generally good for one year from the date your prescriber wrote it. Controlled substances expire sooner: Schedule III, IV, and V prescriptions are void after six months under federal law, and Schedule II prescriptions have no federal expiration but are typically capped by state law somewhere between 60 days and six months. So how long paper prescriptions are good for depends on two things — what drug is on the script and which state’s pharmacy is filling it.
Non-Controlled Medications: One Year Is the Usual Rule
Most states let a pharmacy fill a prescription for a non-controlled drug — think blood pressure medication, cholesterol drugs, antibiotics — for up to one year from the date it was written. That one-year window covers the original fill and any refills the prescriber authorized. A few states set no specific statutory expiration and leave the call to the pharmacist, and at least one state allows validity of up to two years when the prescriber marks the script for ongoing use.
A pharmacist can still refuse to fill a prescription that looks stale inside the legal window. If several months have gone by, the pharmacy may call your doctor to confirm the drug and dose are still right before dispensing, particularly for medications tied to recent lab work. That’s professional judgment, not a legal requirement in most states, but it happens often.
“Refill as needed” or “PRN” notations don’t override the clock. Once your state’s validity period runs out, the prescription is dead no matter how many refills are still printed on the paper. You’ll need a new one.
Schedule II: No Refills, and Usually a State Deadline
Schedule II drugs — opioid painkillers like oxycodone and hydrocodone, stimulants such as amphetamine, and certain sedatives — carry the tightest rules of any commonly prescribed medications.
Federal law bars refills on Schedule II prescriptions entirely. Each fill requires its own prescription. There is no federal expiration date for a Schedule II script, but most states set one, commonly between 60 days and six months. If the prescription is only partially filled, federal law requires the rest to be dispensed within 30 days of the date the prescription was written.1Office of the Law Revision Counsel. 21 USC 829 – Prescriptions
Because refills aren’t allowed, doctors managing ongoing Schedule II therapy often write several prescriptions at one visit, each with a different “do not fill before” date. Federal regulations permit this for up to a 90-day total supply, as long as each individual prescription complies with the rules and the practitioner has determined a legitimate medical need for that quantity.2eCFR. 21 CFR 1306.12 – Refilling Prescriptions; Issuance of Multiple Prescriptions If you receive postdated scripts, each one’s validity clock starts from the date written on that specific prescription.
One practical note: a growing number of states now require controlled substance prescriptions to be transmitted electronically. In those states, your doctor may not be able to hand you a paper Schedule II prescription in the first place, with narrow exceptions for things like technological failures.
Schedules III, IV, and V: Six Months or Five Refills
Drugs in Schedules III through V — including acetaminophen with codeine (III), alprazolam (IV), and certain cough preparations (V) — follow a uniform federal timeline. A prescription for any of these expires six months after the date it was issued.1Office of the Law Revision Counsel. 21 USC 829 – Prescriptions Inside that six-month window, the prescription can be refilled up to five times if the prescriber authorized refills.3eCFR. 21 CFR 1306.22 – Refilling of Prescriptions
Whichever limit you hit first controls. Use all five refills in three months and you need a new prescription even though six months haven’t passed. Reach the six-month mark with refills still on paper and those refills are worthless — the prescription is void and the prescriber has to write a fresh one.3eCFR. 21 CFR 1306.22 – Refilling of Prescriptions This catches people out more than almost any other prescription rule.
State Rules Can Shorten the Federal Window
The Controlled Substances Act sets the floor, not the ceiling. States can impose shorter expiration periods, fewer refills, or extra documentation, and many do. When the two rules disagree, the pharmacist follows whichever is more restrictive. A state that caps Schedule III prescriptions at 90 days overrides the federal six-month allowance for a pharmacy sitting in that state.
There is no single nationwide answer for how long any given prescription lasts. Your pharmacist is bound by the rules of the state where the pharmacy is located, not the state where your doctor practices. Your pharmacist or state board of pharmacy can tell you exactly what applies where you’re trying to fill.
If You Run Out Before You Can Get a New Prescription
Running out of a maintenance medication before you can reach your doctor is common. More than 40 states give pharmacists some authority to dispense an emergency supply of a non-controlled maintenance drug when the prescriber can’t be reached and stopping abruptly could harm the patient. The typical emergency supply is 72 hours, though some states allow 30 days or more for continuation of therapy.
Controlled substances are handled far more strictly. A pharmacist can dispense a Schedule II drug on an oral emergency authorization from the prescriber, but the prescriber must send a written prescription within seven days, and if it never arrives, the pharmacist has to notify the DEA.4eCFR. 21 CFR Part 1306 – Prescriptions for Controlled Substances Listed in Schedule II Pharmacists cannot dispense a controlled substance in an emergency on their own authority.
What to Do With an Expired Paper Prescription
If the script in your hand is past its expiration, call the prescriber’s office. The doctor or their staff will decide whether the medication is still appropriate and can issue a new prescription, often electronically to the pharmacy of your choice, which is faster than another paper script.
Do not change the date on an expired prescription. For controlled substances, obtaining drugs by forgery or fraud is a federal felony carrying up to four years in prison.5Office of the Law Revision Counsel. 21 USC 843 – Prohibited Acts C For non-controlled drugs, every state has a fraud or forgery statute that reaches the same conduct. Pharmacists are trained to spot altered prescriptions, and being flagged in pharmacy databases will make legitimate prescriptions harder to fill going forward.