TEMARIL
Clinical safety rating: caution
Comprehensive clinical and safety monograph for TEMARIL (TEMARIL).
Temaril (trimeprazine tartrate and prednisolone) combines an antipruritic phenothiazine antihistamine with a corticosteroid. Trimeprazine blocks histamine H1 receptors, reducing pruritus and allergic reactions. Prednisolone suppresses inflammation via glucocorticoid receptor activation, inhibiting phospholipase A2 and cytokine production.
| Metabolism | Trimeprazine: Hepatic metabolism via CYP2D6 and other enzymes; active metabolites. Prednisolone: Hepatic metabolism primarily via 11β-hydroxysteroid dehydrogenase, conjugated and excreted renally. |
| Excretion | Primarily via kidneys as metabolites; unchanged drug accounts for <1%. Biliary/fecal excretion is minor. Approx. 90% recovered in urine within 24 hours. |
| Half-life | Terminal elimination half-life is 9–12 hours in adults; prolonged in hepatic impairment (up to 20 hours). Given TID dosing, steady state is reached within 2 days. |
| Protein binding | Approximately 90% bound to plasma proteins, primarily albumin. |
| Volume of Distribution | Vd is 8–13 L/kg, indicating extensive tissue distribution. Higher Vd in children (approx. 15 L/kg). |
| Bioavailability | Oral: 70–80% due to first-pass metabolism. Rectal: ~50% due to partial avoidance of first-pass. IM: ~100%. |
| Onset of Action | Oral: 30–60 minutes for antihistamine effect; peak effect at 2–3 hours. Rectal: 45–90 minutes. IM: 20–30 minutes. |
| Duration of Action | Antihistamine effect lasts 12–24 hours; antiemetic effect persists for 8–12 hours. Clinical duration may be shorter in children. |
| Molecular Weight | 373.52 |
2.5 mg orally twice daily or 5 mg orally at bedtime; maximum 10 mg/day.
| Dosage form | SYRUP |
| Renal impairment | No specific guidelines; use caution with severe renal impairment (CrCl <30 mL/min) due to risk of accumulation. |
| Liver impairment | Contraindicated in severe hepatic impairment (Child-Pugh class C). For Child-Pugh class B, reduce dose by 50%. No adjustment needed for Child-Pugh class A. |
| Pediatric use | Children 12 years and older: same as adult dose. Children 6-11 years: 2.5 mg at bedtime or 1.25 mg every 6 hours as needed; maximum 5 mg/day. Children <6 years: not recommended. |
| Geriatric use | Initiate at 2.5 mg once daily at bedtime; increase cautiously. Increased risk of sedation, confusion, and anticholinergic effects. Avoid in frail elderly. |
| 1st trimester | Avoid; limited human data, animal studies show teratogenicity at high doses. Use only if benefit outweighs risk. |
| 2nd trimester | Avoid; potential for maternal hypotension and fetal hypoxia. Use only if clearly needed. |
| 3rd trimester | Avoid near term; risk of neonatal respiratory depression, irritability, and withdrawal if used chronically. |
Clinical note
Comprehensive clinical and safety monograph for TEMARIL (TEMARIL).
| Placental transfer | Trimeprazine crosses the placenta; fetal concentrations may approach maternal levels. |
| Breastfeeding | Trimeprazine is excreted into breast milk in small amounts; however, effects on the infant are unknown. Possible sedation and apnea in neonates. Use caution, especially in premature infants. |
■ FDA Black Box Warning
No FDA black box warning
| Serious Effects |
Hypersensitivity to trimeprazine or any phenothiazineComatose statesConcurrent use of CNS depressants (e.g., alcohol, barbiturates) due to additive effectsSevere bone marrow suppressionAngle-closure glaucomaProstatic hypertrophy with urinary retentionSevere hypotension
| Precautions | Corticosteroid-related: adrenal suppression, increased susceptibility to infections, gastrointestinal ulceration, osteoporosis, and growth suppression in young animals, Phenothiazine antihistamine: potential for sedation, extrapyramidal symptoms, anticholinergic effects (e.g., dry mouth, urinary retention), Use with caution in animals with diabetes mellitus, heart failure, or renal disease, Avoid abrupt discontinuation after prolonged use to prevent adrenal insufficiency |
| Food/Dietary | Avoid alcohol. No known food interactions; take with food if gastrointestinal upset occurs. |
Loading safety data…
| Lactation Rating |
| L3 (Moderately Safe) - limited data suggest minimal risk but monitor infant for sedation. |
| Teratogenic Risk | TEMARIL (trimeprazine/phenylephrine/phenylpropanolamine combination) is generally not recommended in pregnancy, especially first trimester, due to potential teratogenic effects from antihistamine and sympathomimetic components. Data are limited; however, phenothiazines have been associated with congenital malformations when used early in pregnancy. In second and third trimesters, risk of maternal and fetal tachycardia, uterine contractions, and reduced placental perfusion exists due to vasoconstrictors. Avoid use unless benefit outweighs risk. |
| Fetal Monitoring | Monitor maternal heart rate, blood pressure, and signs of uterine hypertonicity. Fetal heart rate monitoring recommended if used near term. Assess for neonatal respiratory depression, sedation, and feeding difficulties after delivery. |
| Fertility Effects | No specific human data. Antihistamines may theoretically alter ovulation via anticholinergic effects; sympathomimetics can affect hormonal balance. Animal studies have shown reduced fertility at high doses. Clinical significance unknown. |
| Clinical Pearls | TEMARIL (trimeprazine) is a phenothiazine antihistamine with sedative and antipruritic properties, often used in pruritus. Avoid in patients with CNS depression, coma, or history of phenothiazine hypersensitivity. Monitor for extrapyramidal symptoms, especially in pediatric and elderly patients. May cause false-positive pregnancy tests and interfere with urinary 5-HIAA and VMA measurements. Potentiates CNS depressants; reduce dose of concurrent sedatives. |
| Patient Advice | Take exactly as prescribed; do not exceed dose. · May cause drowsiness; avoid driving or operating heavy machinery until you know how it affects you. · Avoid alcohol and other sedatives. · May cause dry mouth; use sugarless candy or ice chips. · Report any unusual muscle movements, especially in the face or neck. · Do not use for asthma or lower respiratory tract symptoms. · Store at room temperature away from light and moisture. |