Demerol (Meperidine) at a glance: schedule, half-life, and class
- Generic name
- Meperidine hydrochloride
- Brand names
- Demerol
- Other names
- Pethidine
- Drug class
- Synthetic opioid agonist (phenylpiperidine)
- US legal status
- Schedule II, prescription only
- Approved uses
- Acute pain severe enough to require an opioid; before and during surgery and labor (injection)
- Forms
- Tablets, oral solution, injection
- Onset
- 15 to 45 minutes
- Half-life
- 3 to 5 hours; its metabolite normeperidine lasts 15 to 30 hours
- Reversal agent
- Naloxone (does not reverse normeperidine seizures)
Demerol uses: what meperidine is prescribed for
Meperidine is approved for acute pain severe enough to require an opioid. Its injection is used before and during surgery, and in labor, though safer opioids have largely replaced it.[1]
Guidelines advise against meperidine for chronic pain and in older adults. With repeated doses it builds up a metabolite, normeperidine, that irritates the nervous system and can cause tremor, twitching, agitation, and seizures, especially in people with kidney disease.[1][2]
Demerol dosage: how meperidine is usually prescribed
The figures below come from the FDA-approved label and describe how prescribers typically use meperidine. They are not personal dosing advice. A prescriber sets the dose for each person and adjusts it over time.[1]
| Product | Typical adult dose | Notes from the label |
|---|---|---|
| Tablets or oral solution, adults | 50 to 150 mg every 3 to 4 hours as needed | Use the lowest dose for the shortest time |
| Kidney impairment | Avoid or use with great caution | Normeperidine accumulates and can cause seizures |
| Older adults | Generally avoided | Listed as potentially inappropriate in older adults |
Demerol (meperidine) side effects and risks
FDA boxed warnings
- Addiction, abuse, and misuse, which can lead to overdose and death.
- Life-threatening slowed breathing, especially when starting treatment or after a dose increase.
- Accidental ingestion, especially by children, can cause a fatal overdose.
- Use with benzodiazepines or other central nervous system depressants, including alcohol, can cause profound sedation, slowed breathing, coma, and death.[3]
- Prolonged use during pregnancy can cause neonatal opioid withdrawal syndrome, which may be life-threatening if not recognized and treated.
- Use with MAO inhibitors, or within 14 days of stopping one, can cause coma, severe breathing problems, unstable blood pressure, and death. This combination is contraindicated.
Common side effects include lightheadedness, dizziness, sedation, nausea, vomiting, and sweating.[1]
Normeperidine toxicity: shakiness, muscle twitching, agitation, and seizures can occur with high doses, repeated dosing, or kidney impairment. Naloxone does not reverse these effects.[1]
Serotonin syndrome: meperidine has serotonin activity. The 1984 death of Libby Zion, who received meperidine while taking an MAO inhibitor, led to major reforms in US hospital training.
Demerol interactions: what not to mix with meperidine
Choose what it would be combined with:
| Combined with | What happens | Label guidance |
|---|---|---|
| Benzodiazepines (alprazolam, diazepam, clonazepam) | Profound sedation, slowed breathing, coma, death | Boxed warning; avoid unless no alternative |
| Alcohol | Stronger sedation and slowed breathing | Avoid |
| Gabapentin, pregabalin, sleep medicines, muscle relaxants | Additive sedation and breathing problems | Use caution; lower doses |
| MAO inhibitors (phenelzine, tranylcypromine, selegiline, linezolid) | Coma, high fever, blood pressure swings, death | Contraindicated, including within 14 days |
| SSRIs, SNRIs, tricyclics, triptans | Serotonin syndrome | Use caution |
| Ritonavir, phenytoin | More normeperidine and seizure risk | Avoid |
This is not a full list. A pharmacist can check a complete medication list, including supplements and over-the-counter products.[1]
Demerol overdose: signs of meperidine overdose and what to do
Meperidine overdose causes slow or stopped breathing, pinpoint pupils, and unconsciousness. It can also cause tremor and seizures from normeperidine, which may continue after naloxone restores breathing.[1][4]
If someone may have overdosed
- Call 911 if the person is unresponsive, cannot be woken, has blue or gray lips, or is breathing slowly or not at all.
- Give naloxone (Narcan or a generic nasal spray, sold without a prescription) into one nostril. If there is no response after 2 to 3 minutes, give another dose.
- If you are trained, give rescue breaths. Otherwise place the person on their side so they do not choke.
- Stay with them. Naloxone can wear off before meperidine does, so the overdose can return even after the person wakes up.
- Most states have Good Samaritan laws that protect people who call 911 for an overdose from some drug charges.
Demerol withdrawal timeline: how long meperidine withdrawal lasts
People who take meperidine regularly for more than a few weeks become physically dependent, even when they take it exactly as prescribed. Dependence is not the same as addiction, but it means stopping suddenly causes withdrawal.[1]
- 3 to 12 hoursEarly symptomsAnxiety, restlessness, yawning, sweating, runny nose, watery eyes, and muscle aches.
- Days 1 to 3Peak withdrawalDiarrhea, stomach cramps, nausea and vomiting, goosebumps, dilated pupils, fast heartbeat, and strong cravings. Rarely dangerous in healthy adults, but dehydration can be serious.
- Days 5 to 10, then weeksLingering symptomsPoor sleep, low mood, low energy, and cravings can continue for weeks. Tolerance falls quickly, which raises the risk of overdose if use restarts.
Warning: After a break, the body loses tolerance within days. Returning to a previous dose of meperidine can cause a fatal overdose.
The FDA warns against stopping opioids abruptly in people who are physically dependent. A prescriber can taper the dose gradually, often by 10% or less per month for long-term users, and medicines such as clonidine or lofexidine can ease symptoms. For opioid use disorder, buprenorphine and methadone cut the risk of death roughly in half.[2]
How to get prescribed Demerol (meperidine) legally in the US
In the United States, meperidine is a Schedule II controlled substance. The only legal way to get it is with a prescription from a clinician registered with the Drug Enforcement Administration (DEA), filled by a licensed pharmacy. Depending on state law, that can be a physician, nurse practitioner, or physician assistant.[5]
- Refills: Schedule II prescriptions cannot be refilled. A prescriber can issue several prescriptions at once, each dated with the earliest fill date, for up to a 90-day supply.[6]
- Telehealth: federal flexibilities let DEA-registered clinicians prescribe Schedule II to V medicines after a telemedicine visit, without a prior in-person exam, through December 31, 2026. A permanent DEA rule was under final review in late 2026. State rules can be stricter.[7]
- Monitoring: prescribers and pharmacists in most states check a prescription drug monitoring program, a database of controlled-substance prescriptions, before prescribing or dispensing.
- Pharmacies: a legitimate pharmacy always requires a valid prescription, has a licensed pharmacist available, and is licensed in the state it ships to. The FDA's BeSafeRx tool and the NABP's safe pharmacy list help confirm a pharmacy is real.[8][9]
- Cost: meperidine is rarely stocked by retail pharmacies, which may need to order it.
Traveling: keep the medicine in its original pharmacy container and carry a copy of the prescription. Check the rules of the destination country before travel, because many countries restrict controlled medicines or require a permit.
Can you order Demerol (meperidine) online legally?
Yes, but only with a valid prescription and only from a pharmacy licensed in your state. Many licensed pharmacies, including mail-order pharmacies run by insurers, fill meperidine prescriptions online and ship them. Buying meperidine from a website that does not require a prescription is illegal, and the product is often fake.[8][10]
- See a licensed clinicianA clinician evaluates you in person or by telemedicine and decides whether meperidine is appropriate.
- The prescription goes to a pharmacyPrescriptions are usually sent electronically, straight from the prescriber to the pharmacy you choose.
- The pharmacy checks and fills itA pharmacist verifies the prescription and your identity, then dispenses the medicine in person or by mail.
Signs that an online seller is illegal:
- It sells meperidine with no prescription, or after only a short online questionnaire.
- It takes orders through social media, messaging apps, or email.
- It asks for payment in cryptocurrency, gift cards, or money transfers.
- It has no US street address, no state pharmacy license, and no pharmacist to speak to.
- Its prices are far below those of ordinary pharmacies, or it ships from another country.
The FDA's BeSafeRx tool links to each state's license lookup, and the National Association of Boards of Pharmacy lists verified online pharmacies.[8][9]
Demerol price: how much does Demerol (meperidine) cost without insurance?
Meperidine is rarely stocked by retail pharmacies, which may need to order it.
What you pay depends on the strength, the number of doses, your insurance plan, and the pharmacy. Cash prices for the same prescription can differ several times over between pharmacies in the same town, so check current prices before you fill it.
Ways to pay less, legally:
- Ask the prescriber whether a generic meperidine is available. FDA-approved generics work the same way as the brand and usually cost much less.
- Compare cash prices between pharmacies before you fill the prescription.
- Use a free prescription discount card, such as GoodRx or SingleCare, when you pay cash. These cards cannot be combined with insurance on the same fill.
- For brand-name medicines, check the manufacturer's savings program or patient assistance program.
- Check your insurer's mail-order pharmacy, which may charge a lower copay.
Warning: A price far below what licensed pharmacies charge, especially with no prescription required, is a strong sign of an illegal seller and counterfeit medicine.[8]
Is Demerol legal? Meperidine legal status in other countries
| Country | Status |
|---|---|
| United Kingdom | Class A (as pethidine) |
| Canada | Schedule I of the Controlled Drugs and Substances Act |
| Australia | Schedule 8 controlled drug |
| International | Schedule I of the 1961 Single Convention on Narcotic Drugs |
Laws change and differ in detail. Check current rules before carrying any controlled medicine across a border.[11]
Common questions about Demerol (meperidine)
Is Demerol still used?
Rarely. Hospitals have mostly replaced it with safer opioids because of seizure risk and dangerous drug interactions.
Why is Demerol (meperidine) dangerous with antidepressants?
With MAO inhibitors it can cause a fatal reaction, and with SSRIs, SNRIs, and other serotonin drugs it can cause serotonin syndrome.
What is normeperidine?
A breakdown product that lasts much longer than meperidine and can cause tremors and seizures as it builds up.
Is pethidine the same as Demerol (meperidine)?
Yes. Pethidine is the international name; meperidine is the US name for the same drug.
Is Demerol (meperidine) used for shivering after surgery?
Small injected doses are sometimes used to stop shivering after anesthesia, an effect other opioids have less.
Can you buy Demerol (meperidine) without a prescription?
No. Demerol (meperidine) is a Schedule II controlled substance in the US, so it is illegal to buy or possess it without a valid prescription. Websites and social media sellers that offer it without one are not legal pharmacies, and the DEA warns that pills sold this way are often counterfeit and can contain fentanyl. The legal route is a visit with a licensed clinician, in person or by telehealth, and a prescription filled at a state-licensed pharmacy. The FDA's BeSafeRx tool and the NABP's safe pharmacy list help confirm an online pharmacy is real.
Sources
- Demerol (meperidine) prescription information. DailyMed, US National Library of Medicine.
- CDC Clinical Practice Guideline for Prescribing Opioids for Pain, 2022. Centers for Disease Control and Prevention, MMWR.
- FDA warns about serious risks and death when combining opioid pain or cough medicines with benzodiazepines. US Food and Drug Administration, 2016.
- Information about naloxone and nalmefene. US Food and Drug Administration.
- Controlled Substance Schedules. DEA Diversion Control Division.
- 21 CFR 1306.12, Refilling prescriptions; issuance of multiple prescriptions (Schedule II). Electronic Code of Federal Regulations.
- Prescribing controlled substances via telehealth. US Department of Health and Human Services.
- BeSafeRx: Your Source for Online Pharmacy Information. US Food and Drug Administration.
- Safe Pharmacy. National Association of Boards of Pharmacy.
- One Pill Can Kill. US Drug Enforcement Administration.
- International drug control conventions. United Nations Office on Drugs and Crime.
