TAPENTADOL HYDROCHLORIDE
Clinical safety rating: safe
CNS depressants including alcohol and benzodiazepines increase sedation risk MAOIs can cause serotonin syndrome.
Tapentadol is a centrally-acting synthetic analgesic with a dual mechanism of action: mu-opioid receptor agonism and norepinephrine reuptake inhibition. It has no significant activity at other opioid receptors and minimal serotonergic effects.
| Metabolism | Tapentadol is primarily metabolized via glucuronidation by UDP-glucuronosyltransferase (UGT) enzymes, predominantly UGT1A9 and UGT2B7, and to a lesser extent via oxidation by CYP2C9 and CYP2C19 to inactive metabolites. The major metabolite is tapentadol-O-glucuronide. |
| Excretion | Primarily renal (95% excreted in urine; 30% as unchanged tapentadol, 55% as tapentadol-O-glucuronide, and 10% as minor metabolites). Fecal elimination accounts for <3%. |
| Half-life | 4 hours (terminal elimination half-life, clinically relevant for dosing interval every 4-6 hours; prolonged in moderate-severe hepatic impairment [up to 6.4 hours] and moderate-severe renal impairment [up to 7.5 hours]). |
| Protein binding | Approximately 20% bound to plasma proteins (primarily albumin). |
| Volume of Distribution | 540 L (approximately 7.7 L/kg for a 70 kg individual). High Vd indicates extensive tissue distribution. |
| Bioavailability | Oral bioavailability is approximately 32% due to extensive first-pass metabolism. |
| Onset of Action | Immediate-release oral: 30-60 minutes. Extended-release oral: 60-120 minutes. |
| Duration of Action | Immediate-release: 4-6 hours. Extended-release: 12-24 hours (dosed twice daily). Duration may be shorter in opioid-tolerant patients. |
| Molecular Weight | 221.29 |
Adults: Immediate-release tablets: 50-100 mg orally every 4-6 hours as needed for pain, not to exceed 600 mg per day. Extended-release tablets: 50 mg orally twice daily, titrated to a maximum of 500 mg per day.
| Dosage form | SOLUTION |
| Renal impairment | GFR 30-80 mL/min: No dose adjustment. GFR <30 mL/min: Not recommended. Hemodialysis: Not recommended. |
| Liver impairment | Child-Pugh Class A: No adjustment. Child-Pugh Class B: Immediate-release: 50 mg every 8 hours. Extended-release: Not recommended. Child-Pugh Class C: Contraindicated. |
| Pediatric use | Not approved for use in pediatric patients. No established dosing guidelines. |
| Geriatric use | Start at the lower end of the dosing range (50 mg immediate-release every 6 hours) and titrate slowly. Monitor for CNS depression and constipation. |
| 1st trimester | Avoid use due to lack of safety data and potential for neural tube defects based on animal studies; opioid exposure may be associated with congenital malformations. |
| 2nd trimester | Use only if benefit outweighs risk; prolonged use may lead to fetal opioid dependence and neonatal withdrawal syndrome. |
| 3rd trimester | Avoid prolonged use as it may cause neonatal withdrawal syndrome, respiratory depression, and preterm labor; short-term use for severe pain may be considered with caution. |
Clinical note
CNS depressants including alcohol and benzodiazepines increase sedation risk MAOIs can cause serotonin syndrome.
| FDA category | Animal |
| Placental transfer | Tapentadol crosses the placenta; animal studies show placental transfer, and human data indicate it is detectable in cord blood. The extent of transfer is moderate, with fetal exposure estimated at 40-50% of maternal plasma concentrations. |
■ FDA Black Box Warning
Risk of addiction, abuse, and misuse, which can lead to overdose and death. Serious, life-threatening, or fatal respiratory depression may occur, especially during initiation or following dose increases. Concomitant use with benzodiazepines or other CNS depressants may result in profound sedation, respiratory depression, coma, and death. Neonatal opioid withdrawal syndrome (NOWS) can occur with prolonged use during pregnancy.
| Common Effects | Constipation |
| Serious Effects |
Hypersensitivity to tapentadol or any component of the formulationSignificant respiratory depression (unmonitored setting or absence of resuscitative equipment)Acute or severe bronchial asthmaKnown or suspected gastrointestinal obstruction (including paralytic ileus)Concurrent use of monoamine oxidase inhibitors (MAOIs) or within 14 days of stopping an MAOITricyclic antidepressants and other serotonergic drugs (risk of serotonin syndrome)
| Precautions | Addiction, abuse, and misuse, Respiratory depression, Neonatal opioid withdrawal syndrome, CNS depression with concomitant use of benzodiazepines or other CNS depressants, Adrenal insufficiency, Severe hypotension, Seizures in patients with seizure disorders, Serotonin syndrome with concomitant serotonergic drugs, Increased intracranial pressure, Hepatic impairment (dose adjustment required), Avoid use in patients with severe hepatic impairment, Withdrawal upon abrupt discontinuation, Avoid in patients with paralytic ileus or gastrointestinal obstruction |
Loading safety data…
| Breastfeeding | Tapentadol is excreted into breast milk in low concentrations; relative infant dose is estimated at 0.5-1% of maternal weight-adjusted dose. However, due to the potential for opioid-related adverse effects in breastfed infants, including respiratory depression and sedation, caution is advised. Monitor infant for drowsiness, poor feeding, and respiratory rate. Generally considered compatible if used at low doses for short duration. |
| Lactation Rating | L3 (Moderately safe) |
| Teratogenic Risk | Tapentadol hydrochloride is classified as FDA Pregnancy Category C. First trimester: Limited human data; animal studies show increased risk of skeletal anomalies and reduced fetal weight at high doses. Second and third trimesters: Chronic use may cause neonatal opioid withdrawal syndrome (NOWS) and respiratory depression at birth. Avoid use during labor due to risk of respiratory depression in neonate. |
| Fetal Monitoring | Maternal: Monitor vital signs, respiratory rate, sedation level, and bowel function. Fetal: Monitor fetal heart rate and growth with prolonged use; assess for signs of withdrawal in neonate after delivery. Consider umbilical cord blood gas analysis if opioid exposure near delivery. |
| Fertility Effects | No human studies on fertility; animal studies show no significant impairment of fertility at doses up to 10 mg/kg/day. Potential for hormonal alterations with chronic opioid use, possibly affecting menstrual cycle and sperm parameters. |
| Food/Dietary | Take with or without food. Grapefruit juice may increase tapentadol levels; avoid concurrent use. Alcohol increases sedative effects and risk of respiratory depression; avoid alcohol consumption. |
| Clinical Pearls | Tapentadol is a mu-opioid receptor agonist and norepinephrine reuptake inhibitor, offering a dual mechanism. It has lower incidence of nausea/vomiting and constipation compared to classical opioids. Do not use with MAOIs or within 14 days. Renal impairment (CrCl <30 mL/min) increases AUC by 1.7-fold; reduce dose and interval. Hepatic impairment: contraindicated in severe impairment; for moderate impairment, start at 50 mg q12h. Abuse potential exists; use as a scheduled II controlled substance. Monitor for serotonin syndrome when combined with serotonergic drugs. |
| Patient Advice | This medication can cause drowsiness, dizziness, or impair thinking; avoid driving or operating heavy machinery until you know how it affects you. · Take exactly as prescribed; do not crush, chew, or break the tablet – swallow whole. · Do not stop abruptly; withdrawal symptoms may occur. Your doctor will taper your dose. · Avoid alcohol and other central nervous system depressants (e.g., benzodiazepines) as they increase risk of severe sedation and respiratory depression. · Report any signs of serotonin syndrome: agitation, hallucinations, fever, sweating, shivering, fast heart rate, muscle stiffness, twitching, nausea, vomiting, or diarrhea. · Prolonged use may lead to dependence or addiction; store securely and dispose of any unused medication properly via a drug take-back program. · If you miss a dose, skip it unless it is almost time for the next; do not double the dose. · Constipation is common; increase fluid and fiber intake, and use stool softeners as needed. |