Section 01 · Monograph
Ganaxolone
Reviewed Nov 2026FDA label
ZtalmyNeuroactive steroid
- Forms
- Susp: 50mg/mL (110mL bottle)
- Dose
- Weight-based TID with food; titrate to max 21mg/kg TID (28kg or less) or 600mg TID (over 28kg) - CDKL5 seizures, age 2+
- MOA
- Positive allosteric modulator of GABA-A receptors
Indications
- Treatment of seizures associated with CDKL5 deficiency disorder in patients 2 years of age and olderFDA-labeled
Mechanism of Action
- Neuroactive steroid that acts as a positive allosteric modulator of GABA-A receptors (synaptic and extrasynaptic)
Full Dosing
Adult / usual
- Oral suspension 50mg/mL given three times daily with food; weight-based titration (28kg or less: maximum 21mg/kg TID; over 28kg: maximum 600mg TID)
- Follow the titration table in the current label (the October 2025 labeling revised starting doses)
- Shake well and use the oral syringe; discard 30 days after opening
Hepatic
- Reduced dosing in severe hepatic impairment; taper gradually when discontinuing
Contraindications
- None listed in labeling
Drug Interactions
- Strong or moderate CYP3A4/2B6 inducers (carbamazepine, phenytoin, rifampin): avoid or adjust
- UGT inhibitors such as valproate: consider reducing a stable ganaxolone dose
- Additive CNS depression with opioids, benzodiazepines and alcohol
Adverse Effects
- Somnolence and sedation
- Fever, salivary hypersecretion, seizure
- Suicidal ideation (antiseizure drug class effect)
- Withdrawal seizures if stopped abruptly (Schedule V)
Monitoring Parameters
- Sedation and mood
- Seizure frequency
- Gradual taper at discontinuation
Pregnancy & Lactation
- Based on animal data may cause fetal harm; limited human data
- Encourage enrollment in the North American Antiepileptic Drug Pregnancy Registry