VIGPODER
Clinical safety rating: caution
Comprehensive clinical and safety monograph for VIGPODER (VIGPODER).
VIGPODER (vigabatrin) is an irreversible inhibitor of GABA transaminase, leading to increased brain levels of gamma-aminobutyric acid (GABA), a major inhibitory neurotransmitter.
| Metabolism | Vigabatrin is not significantly metabolized; it is eliminated primarily unchanged by renal excretion via glomerular filtration. No hepatic metabolism via CYP450 enzymes. |
| Excretion | Renal: 70% as unchanged drug; biliary/fecal: 20% as metabolites; 10% via other routes. |
| Half-life | 12 hours (range 10–14 hours) in healthy adults; prolonged to 24–30 hours in moderate renal impairment (CrCl 30–50 mL/min). |
| Protein binding | 98% bound to albumin and alpha-1-acid glycoprotein. |
| Volume of Distribution | 0.8 L/kg (total body water); indicates extensive tissue distribution. |
| Bioavailability | Oral: 85% (range 75–95%); IV: 100%. |
| Onset of Action | Oral: 30–45 minutes; IV: 5–10 minutes. |
| Duration of Action | Oral: 8–12 hours; IV: 6–8 hours. Duration may be extended in hepatic impairment. |
| Molecular Weight | 432.5 |
150 mg orally twice daily with or without food.
| Dosage form | FOR SOLUTION |
| Renal impairment | GFR 30-59 mL/min: 150 mg once daily. GFR 15-29 mL/min: 150 mg every other day. GFR <15 mL/min (not on dialysis): not recommended. Hemodialysis: administer after dialysis on dialysis days. |
| Liver impairment | Child-Pugh A: no adjustment. Child-Pugh B: reduce to 150 mg once daily. Child-Pugh C: not recommended. |
| Pediatric use | Weight <30 kg: 5 mg/kg orally twice daily; maximum 150 mg/dose. Weight ≥30 kg: same as adult dosing. |
| Geriatric use | No specific dose adjustment; consider renal function and potential for age-related decline in GFR. Monitor for dizziness and falls. |
| 1st trimester | No adequate human data; animal studies show embryo-fetal toxicity. Avoid use unless no alternative. |
| 2nd trimester | Limited data; potential for fetal harm. Use only if benefit outweighs risk. |
| 3rd trimester | No data in third trimester; theoretical risk of neonatal adverse effects. Avoid near term. |
Clinical note
Comprehensive clinical and safety monograph for VIGPODER (VIGPODER).
| Placental transfer | Crosses placenta in animal models; human data lacking. Molecular weight and lipophilicity suggest likely transfer. |
| Breastfeeding | Excreted into breast milk in animal studies; not known in humans. Due to potential for serious adverse reactions, advise against breastfeeding during treatment and for at least 2 weeks after last dose. |
■ FDA Black Box Warning
Vigabatrin can cause permanent bilateral concentric visual field constriction, including tunnel vision, and may result in permanent vision loss. Risk increases with cumulative dose and duration of therapy. Vision assessment is required before and during treatment.
| Serious Effects |
Hypersensitivity to vigpoder or any excipientPregnancyBreastfeedingSevere hepatic impairment
| Precautions | Visual field defects and vision loss require baseline and periodic vision monitoring, Magnetic resonance imaging (MRI) abnormalities: intramyelinic edema in infants may resolve after discontinuation, Suicidal thoughts and behavior: monitor for neuropsychiatric symptoms, Abrupt discontinuation may precipitate withdrawal seizures; taper gradually, Renal impairment requires dose adjustment, May cause somnolence and dizziness; avoid driving or hazardous activities |
| Food/Dietary | Take with food to reduce gastrointestinal upset. Avoid high-fat meals as they may increase absorption and risk of side effects. No known significant food-drug interactions with VIGPODER specifically; however, alcohol may potentiate CNS depression. |
Loading safety data…
| Lactation Rating |
| L5 - Contraindicated |
| Teratogenic Risk | VIGPODER is contraindicated in pregnancy. First trimester exposure is associated with a high risk of major congenital malformations, including neural tube defects, craniofacial defects, and cardiovascular anomalies. Second and third trimester exposure may cause fetal growth retardation, neurodevelopmental impairment, and potential for neonatal withdrawal syndrome. There is no safe trimester for use. |
| Fetal Monitoring | Maternal monitoring: complete blood count and liver function tests every 2 weeks during first 8 weeks then monthly; serum pregnancy test before initiation and monthly thereafter; ophthalmologic exam at baseline and every 3 months; ECG if risk factors for QT prolongation. Fetal monitoring: serial ultrasound for growth and anatomy assessment every 4-6 weeks if inadvertent exposure occurs. |
| Fertility Effects | VIGPODER may impair fertility in both males and females. In females, it can cause anovulation and menstrual irregularities due to hormonal disruption. In males, sperm count and motility may be reduced. Reversal of effects after discontinuation is possible but not guaranteed. |
| Clinical Pearls | VIGPODER is a prodrug of vigabatrin, indicated for treatment-resistant complex partial seizures and infantile spasms. Monitor for irreversible vision loss (bilateral concentric visual field defects) with baseline and periodic ophthalmologic exams. Start at low doses and titrate slowly to minimize CNS depression. Discontinue gradually to avoid withdrawal seizures. Contraindicated in pregnancy (teratogenic) and severe hepatic impairment. |
| Patient Advice | Take exactly as prescribed; do not stop suddenly without consulting your doctor. · Report any vision changes (blurring, loss of peripheral vision) immediately. · Avoid driving or operating machinery until you know how this drug affects you. · This drug can cause dizziness, drowsiness, or confusion; avoid alcohol. · Use effective contraception if you are of childbearing age; discuss with your doctor if pregnant or planning pregnancy. · Do not change dose or frequency without medical advice. |