Antiepileptic — AMPA Receptor Antagonist Pregnancy: Not recommended during pregnancy — limited data (fewer than 300 pregnancy outcomes). Not recommended in women of childbearing potential not using contraception unless clearly necessary; perampanel may reduce the effectiveness of progestogen-containing hormonal contraceptives so an additional non-hormonal method is recommended. Breast-feeding: excretion in human milk is unknown and a risk to the newborn/infant cannot be excluded — decide whether to discontinue breast-feeding or perampanel (section 4.6).

Perampanel

Brand names: Fycompa

Perampanel is an oral antiseizure medication used as adjunctive therapy for focal seizures, with or without secondary generalisation, and for primary generalised tonic-clonic seizures.

Auto-extracted from the source labelling — not yet independently clinician-verified. These values were distilled from the UK SPC (or the US label where noted) but have not had a clinician sign-off. Confirm against the current SmPC before prescribing.

Adult dose

Dose: Partial-onset seizures (adults and adolescents aged 12 years and over): initiate at 2 mg/day and increase by increments of 2 mg based on clinical response and tolerability to a maintenance dose of 4 mg/day to 8 mg/day; depending on response and tolerability at 8 mg/day the dose may be increased by 2 mg/day increments to 12 mg/day

Route: Oral (film-coated tablets; an oral suspension formulation is also available)

Frequency: Once daily at bedtime

Max: 12 mg/day

Perampanel must be titrated according to individual patient response to optimise the balance between efficacy and tolerability. Titration interval: increments no more frequently than every 2 weeks in patients taking concomitant medicinal products that do NOT shorten the half-life of perampanel, and no more frequently than every 1 week in patients taking concomitant products that DO shorten its half-life (see SPC section 4.5). Primary generalised tonic-clonic seizures (adults and adolescents 12 years and over): initiate at 2 mg/day, increase by 2 mg increments to a maintenance dose of up to 8 mg/day; the SPC table gives a recommended maximum dose of 12 mg/day. Paediatric dosing in the SPC is by weight band, not per kg — children 4-11 years (partial-onset) or 7-11 years (primary generalised tonic-clonic): weighing 30 kg or more, start 2 mg/day, titrate in 2 mg steps, maintenance 4-8 mg/day, maximum 12 mg/day; weighing 20 to under 30 kg, start 1 mg/day, titrate in 1 mg steps, maintenance 4-6 mg/day, maximum 8 mg/day (increments of 1 mg/day above 6 mg/day); weighing under 20 kg, start 1 mg/day, titrate in 1 mg steps, maintenance 2-4 mg/day, then 0.5 mg/day increments above 4 mg/day, maximum 6 mg/day. Verify all paediatric dosing against a children's formulary. US labelling states a different maintenance range (8 mg to 12 mg once daily for partial-onset seizures, 8 mg once daily for primary generalised tonic-clonic seizures) and a higher starting dose of 4 mg once daily when a moderate or strong CYP3A4 inducer is co-prescribed (openFDA) — the UK SPC values above take precedence. Hepatic impairment (US labelling): maximum recommended daily dose 6 mg in mild and 4 mg in moderate impairment; not recommended in severe hepatic impairment.

Dose adjustments

Renal

Not stated in the fetched eMC section 4.2 extract. US labelling: may be used in moderate renal impairment with close monitoring and a slower titration may be considered; not recommended in severe renal impairment or in patients undergoing haemodialysis (openFDA section 2.5) — verify against the UK SPC.

Dose auto-extracted from UK Summary of Product Characteristics (SPC) via the eMC; US FDA prescribing information (openFDA / DailyMed) — cross-check; US labelling may differ from UK — not yet clinician-verified. Always confirm against the product SmPC and your local formulary before prescribing.

Contraindications

Hypersensitivity to the active substance or to any of the excipients

Side effects

Dizziness and somnolence (very common) — most common reactions leading to discontinuation
Aggression, anger, anxiety, confusional state (common); suicidal ideation and suicide attempt (uncommon); hallucinations and psychotic disorder (uncommon)
Ataxia, dysarthria, balance disorder, gait disturbance and falls (common)
Fatigue, weight increased, decreased appetite, nausea, diplopia, vertigo, back pain (common)
Severe cutaneous adverse reactions — DRESS (drug reaction with eosinophilia and systemic symptoms) and Stevens-Johnson syndrome (frequency not known); withdraw immediately and never re-challenge

Interactions

Moderate and strong CYP3A4 inducers, including enzyme-inducing antiepileptics such as carbamazepine, phenytoin and oxcarbazepine — shorten the half-life of perampanel and lower plasma levels (by approximately 50% to 67% in US labelling); titrate at 1-week rather than 2-week intervals and monitor closely for response and tolerability when such drugs are introduced or withdrawn (eMC section 4.2; openFDA section 7.2)
Progestogen-containing hormonal contraceptives — at doses of 12 mg/day perampanel may decrease their effectiveness (levonorgestrel exposure reduced by approximately 40% in US labelling); additional non-hormonal contraception is recommended (eMC section 4.4; openFDA section 7.1)
Note: the full eMC section 4.5 text was not captured in the fetched source — verify the complete interaction list against the current SPC

Clinical monograph

How it works

It is a selective, non-competitive antagonist of the AMPA glutamate receptor on postsynaptic neurons, reducing excitatory neurotransmission and seizure propagation.

Prescribing in practice

It carries an MHRA warning for serious neuropsychiatric reactions including aggression, hostility, irritability and suicidal ideation, which warrant prompt review and possible withdrawal.
It is taken once daily at bedtime because of dose-related dizziness and somnolence, and is titrated slowly.
Enzyme-inducing antiepileptics can lower its concentration, and it may reduce the effectiveness of some hormonal contraceptives at higher doses.

Monitoring

Monitor for behavioural and mood changes, dizziness, somnolence, gait disturbance and falls, particularly during titration.

Counselling the patient

Take it once a day at bedtime to limit dizziness and drowsiness.
Tell your team or family carers urgently about any new aggression, anger, low mood or thoughts of self-harm.
Avoid alcohol and use alternative or additional contraception if advised, as it can affect the pill at higher doses.

Evidence & guidelines

Pivotal randomised controlled trials supported its licensing as adjunctive therapy, and the MHRA has issued specific guidance on its neuropsychiatric and behavioural risks.

Reference: NICE NG217; MHRA Fycompa Safety Update; Drug verified in RxNorm (NLM); confirm dosing against the manufacturer SPC (eMC). Verify against your local formulary and current prescribing references before prescribing. The structured dose values shown have been reviewed by a clinician. Monograph status: clinician-reviewed (2026-07-04).

Curated clinical cross-links plus same-class fallbacks.

Calculators

Myasthenia Gravis Activities of Daily Living (MG-ADL) Scale · Neuromuscular

Pathways