Pethidine Stats & Data
CCOC(=O)C1(CCN(C)CC1)c1ccccc1XADCESSVHJOZHK-UHFFFAOYSA-NPharmacology
DrugBankDescription
A narcotic analgesic that can be used for the relief of most types of moderate to severe pain, including postoperative pain and the pain of labor. Prolonged use may lead to dependence of the morphine type; withdrawal symptoms appear more rapidly than with morphine and are of shorter duration.
Mechanism of Action
Meperidine is primarily a kappa-opiate receptor agonist and also has local anesthetic effects. Meperidine has more affinity for the kappa-receptor than morphine. Opiate receptors are coupled with G-protein receptors and function as both positive and negative regulators of synaptic transmission via G-proteins that activate effector proteins. Binding of the opiate stimulates the exchange of GTP for GDP on the G-protein complex. As the effector system is adenylate cyclase and cAMP located at the inner surface of the plasma membrane, opioids decrease intracellular cAMP by inhibiting adenylate cyclase. Subsequently, the release of nociceptive neurotransmitters such as substance P, GABA, dopamine, acetylcholine and noradrenaline is inhibited. Opioids also inhibit the release of vasopressin, somatostatin, insulin and glucagon. Opioids close N-type voltage-operated calcium channels (OP2-receptor agonist) and open calcium-dependent inwardly rectifying potassium channels (OP3 and OP1 receptor agonist). This results in hyperpolarization and reduced neuronal excitability.
Pharmacodynamics
Meperidine is a synthetic opiate agonist belonging to the phenylpiperidine class. Meperidine may produce less smooth muscle spasm, constipation, and depression of the cough reflex than equivalent doses of morphine. The onset of action is lightly more rapid than with morphine, and the duration of action is slightly shorter. The chemical structure of meperidine is similar to local anesthetics. Meperidine is recommended for relief of moderate to severe acute pain and has the unique ability to interrupt postoperative shivering and shaking chills induced by amphotericin B. Meperidine has also been used for intravenous regional anesthesia, peripheral nerve blocks and intraarticular, epidural and spinal analgesia. Meperidine is considered a second-line agent for the treatment of acute pain.
Metabolism
Meperidine is metabolized in the liver by hydrolysis to meperidinic acid followed by partial conjugation with glucuronic acid. Meperidine also undergoes N-demethylation to normeperidine, which then undergoes hydrolysis and partial conjugation. Normeperidine is about half as potent as meperidine, but it has twice the CNS stimulation effects.
Absorption
The oral bioavailability of meperidine in patients with normal hepatic function is 50-60% due to extensive first-pass metabolism. Bioavailability increases to 80-90% in patients with hepatic impairment (e.g. liver cirrhosis). Meperidine is less than half as effective when administered orally compared to parenteral administration. One study reported that 80-85% of the drug administered intramuscularly was absorbed within 6 hours of intragluteal injection in health adults; however, inter-individual variation and patient-specific variable appear to cause considerable variations in absorption upon IM injection.
Indication
Used to control moderate to severe pain.
Half-life
Initial distribution phase (t1/2 α) = 2-11 minutes; terminal elimination phase (t1/2 β) = 3-5 hours. In patients with hepatic dysfunction (e.g. liver cirrhosis or active viral hepatitis) the t1/2 β is prolonged to 7-11 hours.
Protein Binding
60-80% bound to plasma proteins, primarily albumin and α1-acid glycoprotein. The presence of cirrhosis or active viral hepatitis does not appear to affect the extent of protein binding.
Elimination
Excreted in the urine. The proportion of drug that is excreted unchanged or as metabolites is dependent on pH. When urine pH is uncontrolled, 5-30% of the meperidine dose is excreted as normeperidine and approximately 5% is excreted unchanged. Meperidine and normeperidine are found in acidic urine, while the free and conjugated forms of meperidinic and normperidinic acids are found in alkaline urine.
Volume of Distribution
Meperidine crosses the placenta and is distributed into breast milk.
Receptor Profile
Receptor Actions
Receptor Binding
Effect Profile
Curated + 19 ReportsStrong euphoria and pain relief with moderate itching/nausea, mild sedation
Tolerance & Pharmacokinetics
drugs.wikiTolerance Decay
Experience Report Analysis
ErowidDemographics
Gender Distribution
Age Distribution
Reports Over Time
Effect Analysis
ErowidEffects aggregated from 19 experience reports (19 Erowid)
Effect Sentiment Distribution
Confidence Distribution
Positive Effects 8
Adverse Effects 3
Real-World Dose Distribution
62K DosesFrom 29 individual dose entries
Oral (n=10)
Insufflated (n=7)
Form / Preparation
Most common forms and preparations reported
Body-Weight Dosing
Dose relative to body weight from reports with weight data
Redose Patterns
Redosing behavior across 14 reports
Opioid Equivalence (MME)
NIH HEAL 2024 & CDC 2022Pethidine (meperidine) 100 mg oral ≈ 10 mg Morphine oral
Legal Status
| Country | Status | Notes |
|---|---|---|
| Switzerland | Pethidine is a controlled substance specifically named under Verzeichnis A. | Medicinal use is permitted. |
| Turkey | Pethidine is a 'red prescription' only substance and illegal when sold or possessed without a prescription. | |
| United States | Schedule II | Caution : All legal information should be verified through other sources. see below U.S. FEDERAL LEGAL SUMMARY Meperidine - REGULATED: Yes - STATUS: Scheduled - SCHEDULE: Schedule II - CLASSIFICATION: Opiate Meperidine is Schedule II in the United States. This means it is illegal to sell without a DEA license and illegal to buy or possess without a license or prescription. |
References
Data Sources
Cited References
- Edwards et al. 1982 - Clinical Pharmacokinetics of Pethidine
- Erowid: Meperidine Vault
- Gillman 2005 - MAOIs, Opioid Analgesics and Serotonin Toxicity
- Latta et al. 2002 - Meperidine: A Critical Review
- Meperidine - StatPearls NCBI
- Siegel et al. 1982 - Heroin Overdose Death and Drug-Associated Environmental Cues
- Walker & Zacny 1999 - Subjective Effects of Cumulative Opioid μ Agonist Doses