CONZIP
Clinical safety rating: caution
Comprehensive clinical and safety monograph for CONZIP (CONZIP).
Tramadol hydrochloride (opioid agonist) and acetaminophen (centrally acting analgesic). Tramadol binds to mu-opioid receptors and inhibits serotonin and norepinephrine reuptake; acetaminophen inhibits cyclooxygenase (COX) and activates descending serotonergic pathways.
| Metabolism | Tramadol: hepatic via CYP2D6 and CYP3A4 to active M1 metabolite; acetaminophen: hepatic via conjugation (glucuronidation, sulfation) and CYP2E1 (minor). |
| Excretion | ~60% renal (unchanged drug and glucuronide conjugates), ~35% fecal |
| Half-life | Terminal elimination half-life: 3-4 hours for tramadol, 5-9 hours for M1 metabolite; clinically, dosing interval is 4-6 hours |
| Protein binding | ~20% bound to plasma proteins (primarily albumin) |
| Volume of Distribution | 3.9 L/kg (tramadol), indicating extensive tissue distribution |
| Bioavailability | Oral: 75% (immediate-release); extended-release: ~100% relative to immediate-release |
| Onset of Action | Oral: 1 hour (immediate-release); extended-release: 2 hours |
| Duration of Action | Oral immediate-release: 4-6 hours; extended-release: 12-24 hours (up to 24 hours with CONZIP ER) |
| Action Class | Fungal ergosterol synthesis inhibitor |
| Brand Substitutes | Fluent 150mg Tablet, Odicon 150 Tablet, Gocan 150mg Tablet, Fluka 150 Tablet, Fusys 150 Tablet |
100 mg to 300 mg orally once daily with food. Initiate at 100 mg daily and titrate up by 100 mg increments every 4-7 days based on tolerability. Maximum dose 300 mg daily.
| Dosage form | CAPSULE, EXTENDED RELEASE |
| Renal impairment | For creatinine clearance (CrCl) 60-89 mL/min: no adjustment. For CrCl 30-59 mL/min: reduce dose by 30% (e.g., start 70 mg daily). For CrCl 15-29 mL/min: reduce dose by 50% (e.g., start 50 mg daily). For CrCl <15 mL/min: not recommended. Hemodialysis: administer dose after dialysis on dialysis days; reduce dose by 70%. |
| Liver impairment | For Child-Pugh Class A (mild): no adjustment. For Child-Pugh Class B (moderate): reduce dose by 50% (e.g., start 50 mg daily). For Child-Pugh Class C (severe): not recommended (or maximum 50 mg daily with caution). |
| Pediatric use | Safety and efficacy not established in pediatric patients (<18 years). No recommended dosage. |
| Geriatric use | For patients ≥65 years: initiate at 100 mg daily. Use caution and monitor for confusion and sedation. Consider reducing dose to 50 mg daily if tolerability issues arise. |
| 1st trimester | Consult provider |
| 2nd trimester | Consult provider |
| 3rd trimester | Consult provider |
Clinical note
Comprehensive clinical and safety monograph for CONZIP (CONZIP).
| Breastfeeding | Tramadol is excreted into breast milk. M/P ratio approximately 0.94 for tramadol and 0.8 for O-desmethyltramadol (active metabolite). Infant exposure estimated at 2.24% of maternal weight-adjusted dose. May cause drowsiness or poor feeding in infants; not recommended during breastfeeding unless benefit outweighs risk. |
| Teratogenic Risk | CONZIP (tramadol hydrochloride) is FDA Pregnancy Category C. In first trimester, cross-reactivity with opioid receptors raises concern for neural tube defects based on animal studies; human data limited but not excluded. In second and third trimesters, prolonged use may cause fetal opioid dependence and neonatal abstinence syndrome (NAS). Near term, use may lead to respiratory depression in the neonate. |
■ FDA Black Box Warning
Addiction, abuse, and misuse; life-threatening respiratory depression; accidental ingestion (especially in children); ultra-rapid metabolism of tramadol to O-desmethyltramadol (M1) in CYP2D6 poor metabolizers leading to toxicity; neonatal opioid withdrawal syndrome with prolonged use during pregnancy; risks from concomitant use with benzodiazepines or other CNS depressants.
| Serious Effects |
Hypersensitivity to tramadol, acetaminophen, or any component; significant respiratory depression; acute or severe bronchial asthma; gastrointestinal obstruction (including paralytic ileus); use of MAOIs within 14 days; treatment of acute severe asthma exacerbation; concurrent use of linezolid; known history of prolonged QT interval or QT prolongation risk factors (tramadol component); severe hepatic impairment (acetaminophen).
| Precautions | Respiratory depression; seizure risk (especially with CNS depressants, MAOIs, SSRIs, SNRIs); serotonin syndrome; increased intracranial pressure; severe hypotension; head injury; acute abdominal conditions; renal/hepatic impairment; elderly; debilitated patients; drug dependence; withdrawal; pregnancy; nursing mothers; CYP2D6 ultrarapid metabolizers; concomitant use with alcohol or other CNS depressants. |
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| Fetal Monitoring | Monitor maternal respiratory rate, sedation level, and bowel function. Fetal monitoring: non-stress test (NST) and biophysical profile (BPP) if prolonged use or signs of withdrawal. Neonatal monitoring for respiratory depression, sedation, and NAS (especially with chronic use). |
| Fertility Effects | Tramadol may impair female fertility via prolactin elevation or direct effects on ovarian steroidogenesis, as suggested by animal studies. Human data limited; men may experience reduced libido or erectile dysfunction. Effects are typically reversible upon discontinuation. |