TRIAVIL 4-25
Clinical safety rating: caution
Comprehensive clinical and safety monograph for TRIAVIL 4-25 (TRIAVIL 4-25).
TRIAVIL (amitriptyline/perphenazine) combines a tricyclic antidepressant (amitriptyline) that inhibits reuptake of norepinephrine and serotonin, and a phenothiazine antipsychotic (perphenazine) that blocks dopamine D2 receptors, serotonin 5-HT2 receptors, and alpha-adrenergic receptors, with additional anticholinergic, antihistaminergic, and antiemetic properties.
| Metabolism | Amitriptyline: primarily hepatic via CYP2C19, CYP2D6, CYP3A4; active metabolite nortriptyline. Perphenazine: hepatic metabolism via CYP2D6, CYP3A4, and CYP1A2. |
| Excretion | Renal: ~70% as metabolites (including amitriptyline and perphenazine metabolites) and <5% unchanged; fecal: ~30% via bile; enterohepatic recirculation occurs. |
| Half-life | Amitriptyline: 13–36 hours (mean ~21 hours); perphenazine: 8–21 hours (mean ~12 hours); steady-state achieved in 3–10 days. |
| Protein binding | Amitriptyline: 96% bound to albumin and alpha-1 acid glycoprotein; perphenazine: 90–95% bound to albumin. |
| Volume of Distribution | Amitriptyline: 12–18 L/kg (extensive tissue binding); perphenazine: 10–15 L/kg (large Vd due to lipophilicity). |
| Bioavailability | Oral: Amitriptyline ~50% (first-pass metabolism); perphenazine ~40% (extensive first-pass). |
| Onset of Action | Oral: Antidepressant effect 1–2 weeks, anxiolytic/antipsychotic effect 1–3 days. |
| Duration of Action | Oral: Amitriptyline effect persists 24–48 hours after single dose; perphenazine effect 6–12 hours; extended dosing maintains steady-state levels. |
| Molecular Weight | Amitriptyline: 277.4 Da; Perphenazine: 403.9 Da |
One tablet (perphenazine 4 mg / amitriptyline 25 mg) orally 3 to 4 times daily. Maximum: 8 tablets daily.
| Dosage form | TABLET |
| Renal impairment | No specific dose adjustment guidelines; use with caution in severe renal impairment (CrCl <10 mL/min). Avoid if possible in ESRD. |
| Liver impairment | Child-Pugh A: no adjustment. Child-Pugh B: reduce dose by 50%. Child-Pugh C: contraindicated. |
| Pediatric use | Not recommended for children <12 years. For adolescents ≥12 years: start with 1 tablet (2-10/25) orally 2-3 times daily; titrate to 4-25 strength as needed. Maximum 8 tablets daily. |
| Geriatric use | Start with 1 tablet (2-10/10 or 2-10/25) orally 1-2 times daily; titrate slowly. Reduce total daily dose by 50% compared to younger adults. Maximum 4 tablets daily. Monitor for anticholinergic effects, sedation, and orthostatic hypotension. |
| 1st trimester | Risk of teratogenicity: Amitriptyline associated with cardiovascular malformations; perphenazine associated with neural tube defects and other malformations. Avoid unless benefit outweighs risk. |
| 2nd trimester | Amitriptyline and perphenazine cross placenta. Risk of maternal sedation and orthostatic hypotension. Use only if essential. |
| 3rd trimester | Neonatal withdrawal symptoms and extrapyramidal signs possible with perphenazine. Amitriptyline may cause neonatal irritability, respiratory distress. Avoid near term. |
Clinical note
Comprehensive clinical and safety monograph for TRIAVIL 4-25 (TRIAVIL 4-25).
| Placental transfer | Both drugs cross placenta. Amitriptyline: documented transfer; perphenazine: expected transfer based on molecular size and lipophilicity. |
| Breastfeeding | Both drugs excreted into breast milk. Amitriptyline levels low, but perphenazine may cause sedation, developmental delay. Monitor infant for drowsiness, poor feeding. Use with caution. |
■ FDA Black Box Warning
WARNING: Increased mortality in elderly patients with dementia-related psychosis (perphenazine component). Antidepressants (amitriptyline) may increase risk of suicidal thoughts and behaviors in children, adolescents, and young adults. Not approved for use in pediatric patients.
| Serious Effects |
Hypersensitivity to amitriptyline or perphenazineConcomitant use with MAOIs or within 14 daysRecent myocardial infarction (amitriptyline)Severe CNS depression (perphenazine)Narrow-angle glaucoma (amitriptyline)Bone marrow suppression (perphenazine)Comatose states
| Precautions | Anticholinergic effects (dry mouth, constipation, blurred vision, urinary retention, tachycardia), Cardiovascular toxicity (QT prolongation, arrhythmias, orthostatic hypotension), CNS depression (sedation, impaired motor function, risk of falls), Neuroleptic malignant syndrome (NMS) with perphenazine, Tardive dyskinesia with prolonged perphenazine use, Seizure threshold lowering, Endocrine effects (hyperprolactinemia, gynecomastia, amenorrhea), Hematologic toxicity (agranulocytosis), Hepatic impairment, Serotonin syndrome with other serotonergic drugs |
| Food/Dietary |
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| Lactation Rating | L3 - Moderately Safe |
| Teratogenic Risk | First trimester: Use of amitriptyline/perphenazine (Triavil 4-25) is associated with a small increased risk of congenital malformations, particularly cardiovascular defects with tricyclic antidepressants. Perphenazine is a phenothiazine; first-trimester exposure may increase risk of neural tube defects and cardiac anomalies. Second and third trimesters: Chronic use may cause extrapyramidal symptoms, neonatal withdrawal (irritability, feeding difficulties), and anticholinergic effects in the neonate. Third-trimester use of amitriptyline may increase risk of persistent pulmonary hypertension of the newborn (PPHN). |
| Fetal Monitoring | Maternal: monitor blood pressure, heart rate, liver function, complete blood count, and ECG (due to QT prolongation risk). Assess for extrapyramidal symptoms and anticholinergic effects. Fetal/neonatal: ultrasound for congenital anomalies if first-trimester exposure; monitor neonatal adaptation period for withdrawal, sedation, extrapyramidal signs, and feeding difficulties. |
| Fertility Effects | Hyperprolactinemia due to perphenazine (dopamine receptor antagonist) can cause menstrual irregularities, anovulation, and reduced fertility. Amitriptyline does not significantly affect fertility. Both drugs may affect sexual function. |
| Avoid alcohol and grapefruit juice (may increase amitriptyline levels). High-fiber diets may reduce amitriptyline absorption. Avoid tyramine-rich foods (aged cheeses, cured meats, fermented products) if also taking MAOIs—though contraindicated, this combination risk is critical. Excessive caffeine may worsen anxiety or agitation. |
| Clinical Pearls | TRIAVIL 4-25 contains perphenazine 4 mg and amitriptyline 25 mg. Monitor for extrapyramidal symptoms (EPS) and tardive dyskinesia due to perphenazine; use lowest effective dose. Amitriptyline requires ECG monitoring for QTc prolongation, especially in elderly. Avoid abrupt discontinuation due to withdrawal (cholinergic rebound, dyskinesias). Dose reductions of 25-50% may be needed in hepatic impairment. Neuroleptic malignant syndrome (NMS) risk; educate patient on symptoms. |
| Patient Advice | Take exactly as prescribed; do not stop suddenly without consulting your doctor. · Avoid alcohol and other CNS depressants (e.g., benzodiazepines, opioids). · May cause drowsiness, dizziness, or blurred vision; do not drive until you know how it affects you. · Rise slowly from sitting or lying to prevent falls. · Report any uncontrolled muscle movements, especially of the face or tongue, fever, or stiff muscles. · Drink plenty of fluids and use fiber to prevent constipation. · Avoid prolonged sun exposure; use sunscreen. · Do not take MAO inhibitors (e.g., Marplan, Nardil, Parnate) within 14 days. · Contact doctor if you notice rapid heartbeat, fainting, or yellowing of skin/eyes. · Store at room temperature away from moisture and heat. |