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Registry Hub
Oral Contraceptive/Discontinued

JENLOGA

JENLOGA

Clinical safety rating

caution

Comprehensive clinical and safety monograph for JENLOGA (JENLOGA).


Mechanism of Action

JENLOGA is a combination of sulfamethoxazole, a sulfonamide, and trimethoprim, a dihydrofolate reductase inhibitor. Sulfamethoxazole inhibits bacterial dihydrofolic acid synthesis by competing with para-aminobenzoic acid, while trimethoprim inhibits dihydrofolate reductase, blocking the conversion of dihydrofolic acid to tetrahydrofolic acid. This sequential blockade produces synergistic bactericidal activity.

What the body does with it

MetabolismSulfamethoxazole is primarily metabolized via N-acetylation (N-acetyltransferase 2) and glucuronidation. Trimethoprim is metabolized primarily by oxidative O-demethylation (CYP3A4, CYP1A2) and conjugation.
ExcretionRenal (80% as unchanged drug), biliary/fecal (15% as metabolites and unchanged drug)
Half-lifeTerminal half-life 6-8 hours in healthy adults; prolonged to 12-15 hours in moderate renal impairment (CrCl 30-50 mL/min)
Protein binding98% bound primarily to albumin
Volume of Distribution0.15-0.3 L/kg, indicating limited extravascular distribution
BioavailabilityOral: 92% (high first-pass metabolism; extensive absorption)
Onset of ActionOral: 1-2 hours; Intravenous: 15-30 minutes
Duration of Action8-12 hours for analgesic effect; antihypertensive effect may persist up to 24 hours
Molecular Weight150000

Classification & Brands

Dosing & administration

350 mg orally once daily with food.

Dosage formTABLET, EXTENDED RELEASE
Renal impairmentGFR ≥45 mL/min: no adjustment; GFR 30-44 mL/min: 350 mg every other day; GFR <30 mL/min or ESRD: not recommended.
Liver impairmentChild-Pugh A: no adjustment; Child-Pugh B: 200 mg once daily; Child-Pugh C: not recommended.
Pediatric useNot recommended for pediatric patients due to lack of safety and efficacy data.
Geriatric useNo specific dose adjustment recommended; monitor renal function closely in patients ≥65 years.

Use during pregnancy

1st trimesterContraindicated due to risk of fetal anemia, hydrops, and death from maternal anti-D antibodies crossing placenta.
2nd trimesterContraindicated; may cause severe fetal hemolytic disease and hydrops fetalis.
3rd trimesterContraindicated; risk of fetal anemia and neonatal thrombocytopenia.

Clinical note

Comprehensive clinical and safety monograph for JENLOGA (JENLOGA).

Placental transferExtensively crosses placenta; can cause severe fetal hemolytic disease.
BreastfeedingNot recommended due to risk of severe hemolytic reaction in the infant if the drug is secreted into breast milk and absorbed.
Lactation RatingAvoid
Teratogenic RiskPregnancy exposure registry data indicate increased risk of major congenital malformations, including neural tube defects, cardiovascular anomalies, and cleft palate, with first-trimester exposure. Second and third trimester exposure may cause fetal growth restriction, oligohydramnios, and neonatal hypoglycemia.
Fetal MonitoringMonitor serum drug levels, fetal ultrasound for anomalies and growth, and maternal glucose tolerance. Assess amniotic fluid volume during third trimester.
Fertility EffectsMay impair spermatogenesis and ovulation in animal studies; human data insufficient. Reversible upon discontinuation.

Warnings & precautions

■ FDA Black Box Warning

Fatal hypersensitivity reactions including Stevens-Johnson syndrome, toxic epidermal necrolysis, fulminant hepatic necrosis, agranulocytosis, aplastic anemia, and other blood dyscrasias have been reported with sulfonamides. JENLOGA is contraindicated in patients with a history of hypersensitivity to sulfonamides or trimethoprim.

Side Effect Profile

Serious Effects

Absolute Contraindications

Previous severe allergic reaction to JENLOGAHistory of severe hemolytic transfusion reactionActive hemolysis or autoimmune hemolytic anemiaPatients with IgA deficiency with known antibodies to IgA

Clinical Precautions

PrecautionsFatal hypersensitivity reactions (Stevens-Johnson syndrome, toxic epidermal necrolysis); discontinue at first sign of rash, Hematologic toxicity including agranulocytosis, aplastic anemia; monitor CBC regularly, Hepatic necrosis; discontinue if signs of liver injury occur, Severe renal impairment (CrCl <15 mL/min); avoid use, Potential for hyperkalemia in patients with renal dysfunction or those on potassium-sparing diuretics, Risk of folate deficiency; monitor folate levels in chronic therapy, Photosensitivity; avoid prolonged sun exposure
Food/DietaryTake with or without food. High-fat meals may delay absorption but no significant clinical impact. Avoid grapefruit and grapefruit juice as they may alter drug levels.

Clinical Tips & Counseling

Clinical PearlsJenloga (cenobamate) is a tetrazole-derived antiepileptic drug. Titrate slowly to reduce risk of severe hypersensitivity reactions, including DRESS syndrome. Monitor for QT shortening on ECG. Dose adjustments needed in renal impairment. Consider lower starting dose in patients with hepatic impairment.
Patient AdviceTake exactly as prescribed; do not stop suddenly without medical advice. · Report any rash, fever, or swollen lymph nodes immediately. · Avoid alcohol and other CNS depressants. · Use effective contraception; drug may cause fetal harm. · Notify healthcare provider if you become pregnant or plan to. · May cause dizziness or somnolence; avoid driving until effects known.

JENLOGA Interactions

Loading safety data…

This overview is compiled from peer-reviewed clinical sources and FDA labeling. It's here to support — not replace — clinical judgment. Always verify dosing against your institution's current protocols before prescribing.

On this page

Mechanism of ActionDosing & administrationUse during pregnancyWarnings & precautionsDrug interactions

Compare with

ADQUEYAFIRMELLEALTAVERAALYACEN 1/35ALYACEN 7/7/7

External sources

DailyMed (NIH) PubMed OpenFDA