Mechanism of action: Stiripentol balliculeVisual mnemonic: Stiripentol mascot “Die or commit, Stirrup pen doll” Approved as an add-on to clobazam (ONFI, the mascot on the left) for seizures in Dravet syndrome
What it isGABA-A positive allosteric modulator used with clobazam for Dravet syndrome.
Why this oneIts Dravet-specific role includes deliberately increasing clobazam’s active metabolite through CYP inhibition.
What limits itSomnolence, appetite and weight loss, neutropenia, and interactions are common; clobazam often needs reduction.
Pearls
Approved from age 6 months
Molecular structure: Stiripentol
Stiripentol prescription history
Animated chart of estimated U.S. prescriptions per year, Antiseizure meds (1869–2026). Stiripentol enters in 2019 (estimated).
FDA-approved for
Dravet syndrome (2018)
Principal riskmarked sedation from increased clobazam and norclobazam exposure
Seizures with Dravet syndrome (adjunct with clobazam)
≥6 months, ≥7 kg
50 mg/kg/day divided BID or TID
50 mg/kg/day
3000 mg/day
Renal Undefined
Hepatic Undefined
Max 3000 mg/day; do not exceed BID frequency in patients <10 kg (limit free water/overexposure).
Instructions
Capsules: swallow whole with water during a meal; do not break or open.
Oral suspension: mix in water (100 mL) and take immediately during a meal.
Withdraw gradually to minimize risk of increased seizures/status epilepticus.
If somnolence with concomitant clobazam, reduce clobazam by 25%.
Available strengths
cap 250, 500 mg
susp 250, 500 mg/packet
Cautions
Somnolence, esp. with clobazam/other CNS depressants
Decreased appetite and weight — monitor growth in pediatrics
Neutropenia and thrombocytopenia — CBC before treatment and every 6 months
Withdrawal seizures/status epilepticus on abrupt discontinuation
PKU: oral suspension contains phenylalanine
Suicidal behavior and ideation
Adverse reactions
Somnolence
Decreased appetite
Agitation
Ataxia
Weight decreased
Hypotonia
Nausea
Tremor
Dysarthria
Insomnia
Pregnancy No adequate human data; animal developmental toxicity (malformations, mortality) below clinical dose. Enroll in NAAED registry.
Lactation No data on presence in milk or infant effects; weigh benefits/risks.
Cost
Stiripentol (DIACOMIT)
Strength
#/mo
generic $
CostPlus
250 mg
cap
60 BID
not offered
500 mg
cap
60 BID
not offered
250 mg/packet
susp
per unit
not offered
500 mg/packet
susp
per unit
not offered
NADAC is a voluntary CMS survey of what retail community pharmacies pay for the drugs they stock. Stiripentol is dispensed outside retail pharmacies, so it rarely appears on surveyed invoices.