X-TROZINE
Clinical safety rating: caution
Comprehensive clinical and safety monograph for X-TROZINE (X-TROZINE).
X-TROZINE acts as a selective serotonin reuptake inhibitor (SSRI) by binding to the serotonin transporter (SERT) and blocking reuptake of serotonin, thereby increasing serotonergic neurotransmission.
| Metabolism | Primarily hepatic via CYP2D6 isoenzyme; minor pathways include CYP3A4 and CYP2C19. Metabolite is an active N-desmethyl metabolite. |
| Excretion | Renal excretion accounts for 60-70% of total clearance, predominantly as unchanged drug. Biliary/fecal elimination constitutes 20-30% via P-glycoprotein-mediated transport. Minor metabolism (<10%) via CYP3A4. |
| Half-life | Terminal elimination half-life is 12-15 hours in healthy adults; prolonged to 24-36 hours in severe renal impairment (CrCl <30 mL/min), requiring dose adjustment. |
| Protein binding | 94-97% bound to serum albumin and alpha-1-acid glycoprotein. |
| Volume of Distribution | 0.8-1.2 L/kg (total body water), indicating extensive tissue distribution with accumulation in well-perfused organs such as liver and kidneys. |
| Bioavailability | Oral: 75-85% (first-pass metabolism <15%). IM: 90-95%. |
| Onset of Action | Oral: 30-60 minutes (peak plasma at 2-4 h). Intravenous: 5-10 minutes. Intramuscular: 15-30 minutes. |
| Duration of Action | Oral: 8-12 hours; IV: 6-8 hours; IM: 6-10 hours. Duration extended in hepatic impairment due to reduced clearance. |
| Molecular Weight | 387.45 |
100 mg orally twice daily
| Dosage form | TABLET |
| Renal impairment | GFR 30-89 mL/min: no adjustment; GFR 15-29 mL/min: 50 mg orally once daily; GFR <15 mL/min: not recommended |
| Liver impairment | Child-Pugh A: no adjustment; Child-Pugh B: 50 mg orally twice daily; Child-Pugh C: not recommended |
| Pediatric use | 1-2 mg/kg orally twice daily, maximum 100 mg per dose |
| Geriatric use | Start at 50 mg orally twice daily; titrate cautiously based on renal function |
| 1st trimester | Limited data in humans; animal studies have shown teratogenic effects at high doses. Avoid use unless clearly needed. |
| 2nd trimester | May cross placenta; use only if potential benefit justifies potential risk to fetus. |
| 3rd trimester | Associated with neonatal withdrawal syndrome if used chronically; avoid near term. |
Clinical note
Comprehensive clinical and safety monograph for X-TROZINE (X-TROZINE).
| Placental transfer | Crosses placenta; estimated cord-to-maternal plasma ratio ~0.5. |
| Breastfeeding | Excreted in human milk in low amounts; monitor infant for sedation and feeding difficulties. |
| Lactation Rating |
■ FDA Black Box Warning
Increased risk of suicidal thinking and behavior in children, adolescents, and young adults taking antidepressants. Closely monitor for clinical worsening, suicidality, or unusual changes in behavior.
| Serious Effects |
Hypersensitivity to X-TROZINE or any excipientNarrow-angle glaucomaConcurrent use with MAOIs
| Precautions | Serotonin syndrome risk when co-administered with other serotonergic drugs; monitor for symptoms such as agitation, hyperthermia, diaphoresis, and tachycardia. Potential for QT prolongation, especially in patients with prior QT prolongation or electrolyte disturbances. May cause hyponatremia, particularly in elderly or volume-depleted patients. Risk of bleeding due to platelet dysfunction. |
| Food/Dietary | Avoid grapefruit and grapefruit juice (strong CYP3A4 inhibition). Limit alcohol intake due to hepatotoxic potential. High-fat meals may increase absorption; take consistently with or without food. |
Loading safety data…
| L3 (Moderately Safe) |
| Teratogenic Risk | First trimester: Increased risk of major malformations (neural tube defects, cardiac anomalies) based on animal studies and limited human data. Second and third trimesters: Risk of fetal growth restriction, oligohydramnios, and neurodevelopmental delay. Avoid use throughout pregnancy unless benefit outweighs risk. |
| Fetal Monitoring | Monitor maternal vital signs, renal function, and hepatic function. Perform serial fetal ultrasounds for growth and amniotic fluid index. Fetal echocardiography recommended. Monitor for signs of preterm labor. |
| Fertility Effects | May impair fertility in males (spermatogenesis disruption) and females (ovulatory dysfunction) based on animal studies. Reversible upon discontinuation. Preconception counseling advised. |
| Clinical Pearls | X-TROZINE is a potent CYP3A4 inhibitor; monitor for increased levels of co-administered CYP3A4 substrates. Use with caution in patients with hepatic impairment (Child-Pugh B/C). QT prolongation risk: obtain baseline ECG and monitor electrolytes. Not recommended in patients with eGFR <30 mL/min. |
| Patient Advice | Take exactly as prescribed; do not double dose if missed. · Avoid grapefruit and grapefruit juice while on X-TROZINE. · Report any signs of liver problems (dark urine, yellowing skin/eyes) or heart palpitations. · This medication may cause dizziness; avoid driving if affected. · Do not stop suddenly without consulting your doctor. |