What Is Onfi? Uses, Dosage, and What You Need to Know in 2026

Onfi is a prescription medication used to control seizures in people with Lennox-Gastaut syndrome (LGS). It's been FDA-approved since 2011 and has become one of the most widely used adjunctive treatments for this challenging epilepsy syndrome. This guide answers the most common questions about Onfi — what it is, who uses it, how it's dosed, and what you need to know before starting treatment.

What Is Onfi?

Onfi is the brand name for clobazam, a 1,5-benzodiazepine used as an adjunctive (add-on) treatment for seizures. The generic name is clobazam, and it's also available as Sympazan (an oral dissolving film). Unlike most benzodiazepines — which are 1,4-benzodiazepines — clobazam has a unique chemical structure that gives it anticonvulsant properties with somewhat less sedation than drugs like diazepam (Valium) or clonazepam (Klonopin).

Onfi is a Schedule IV controlled substance under DEA regulations, meaning it has a risk of dependence and abuse, though lower than higher-schedule drugs.

What Is Onfi Used For?

The FDA approved Onfi in October 2011 for one indication:

• Adjunctive treatment of seizures associated with Lennox-Gastaut syndrome (LGS) in patients 2 years of age or older.

LGS is a severe form of childhood-onset epilepsy characterized by multiple seizure types (including tonic, atonic, myoclonic, and absence seizures), cognitive impairment, and an abnormal EEG pattern. It's one of the most treatment-resistant epilepsy syndromes, which is why multiple medications are typically used together.

Onfi is also prescribed off-label for a number of other conditions, including:

• Dravet syndrome (a severe genetic epilepsy of infancy)
• Refractory focal (partial-onset) epilepsy in adults
• Catamenial epilepsy (seizures linked to the menstrual cycle)
• Adjunctive therapy for refractory status epilepticus

What Forms Does Onfi Come In?

Clobazam is available in three formulations:

• Onfi tablets: 10 mg and 20 mg white scored tablets. Can be swallowed whole, split in half, or crushed and mixed with applesauce.
• Onfi oral suspension: 2.5 mg/mL, supplied in a 120 mL bottle with oral dosing syringes and a bottle adapter. Berry-flavored. Use within 90 days of opening.
• Sympazan oral film: 5 mg, 10 mg, or 20 mg dissolving film strips placed on top of the tongue. Dissolve without water — do not drink liquids while the film dissolves.

How Is Onfi Dosed?

Clobazam dosing is based on body weight. Your doctor will start you at a low dose and gradually increase it over several weeks:

• Patients weighing 30 kg or less: Start at 5 mg/day. Increase to 10 mg/day after week 1. Maximum dose: 20 mg/day.
• Patients weighing more than 30 kg: Start at 10 mg/day. Increase to 20 mg/day after week 1. Maximum dose: 40 mg/day.

Doses greater than 5 mg/day are given in two divided doses (twice daily). Do not increase the dose more rapidly than once per week, because clobazam and its active metabolite take 5–9 days to reach stable levels in the body.

Lower starting doses and slower titration are recommended for the elderly, patients with liver impairment, and known CYP2C19 poor metabolizers.

How to Take Onfi

Key instructions for taking Onfi correctly:

• Can be taken with or without food
• Take at the same times each day
• Tablets can be crushed and mixed with applesauce if swallowing is difficult
• Shake the oral suspension well before each use; use only the provided dosing syringes
• Never stop Onfi suddenly — always taper gradually under your doctor's guidance
• Store at room temperature (68–77°F). Discard oral suspension 90 days after opening.

Is Generic Clobazam the Same as Onfi?

Yes. Generic clobazam is FDA-approved as therapeutically equivalent to brand-name Onfi. Multiple manufacturers produce generic clobazam tablets, and they contain the same active ingredient in the same doses. Generics are significantly less expensive — typically $30–$150 per month versus $745–$1,000+ for brand Onfi.

Where Can I Find Onfi in Stock?

Onfi and generic clobazam have faced intermittent supply shortages since around 2020. If your pharmacy is out of stock, medfinder can help locate it by calling nearby pharmacies on your behalf. For the full current shortage situation, see our Onfi shortage update for 2026.