primidone at a glance
Medicine class
Antiseizure treatment; barbiturate derivative
Licensed uses
Selected epilepsy types and essential tremor
Administration
Swallow the tablet whole with water
Important precaution
Do not stop suddenly without medical guidance
What is primidone used for?
The selected product is licensed for:
Generalised tonic-clonic epilepsy and psychomotor or temporal-lobe epilepsy
Focal or Jacksonian seizures, myoclonic jerks and akinetic attacks
Essential tremor
How does primidone work?
Primidone reduces seizure activity and can suppress tremor. It is partly converted to phenobarbital and phenylethylmalonamide (PEMA), which are also active. Effects on nerve-cell membranes and ion movement are thought to be important.
primidone preparations and strengths
Tablet
Route: Oral
Strengths: 50 mg, 125 mg, 250 mg
How to take primidone
Take primidone exactly as prescribed and consistently. Swallow the tablet whole with a glass of water. Do not stop abruptly, as withdrawal can provoke seizures or other withdrawal effects. Avoid driving or operating machinery if it causes sleepiness, visual disturbance or slowed reactions.
Tell hospital and dental staff that you take primidone.
Check before drinking alcohol, as sedation may increase.
For epilepsy, do not change manufacturer without discussing this with your prescriber or pharmacist.
primidone side effects
Common or expected effects
- Sleepiness, particularly when starting treatment
- Poor coordination, unsteadiness or abnormal eye movements
- Visual disturbance
- Lack of energy or apathy
- Nausea
Get urgent medical advice
- Blistering, peeling or widespread rash, mouth ulcers or red swollen eyes
- Thoughts of self-harm or suicide
- Fever, rash, swollen glands or signs of severe hypersensitivity
- Unusual bruising, bleeding, pallor or recurrent infection
- New confusion, hallucinations or severe behavioural change
primidone in pregnancy
Primidone is extensively converted to phenobarbital, which is associated with fetal harm. The selected product advises use in pregnancy only when expected benefit outweighs risk after considering alternatives. Primidone-specific pregnancy data are too limited for firm conclusions. Anyone planning pregnancy, pregnant or who may be pregnant should obtain prompt specialist advice and must not stop treatment suddenly.
primidone while breastfeeding
Breastfeeding is not recommended in the selected product information because primidone enters breast milk and may sedate the baby, interfere with feeding and contribute to poor weight gain. Discuss feeding options with the prescriber before breastfeeding or changing treatment.
primidone interactions
Primidone and phenobarbital strongly induce liver enzymes and can reduce the effectiveness of many medicines. An interaction check is important when anything is started, stopped or changed.
Hormonal contraceptives
May be less effective; discuss alternative or additional contraception.
Warfarin and related vitamin K antagonists
Anticoagulant effect may change and closer INR monitoring may be needed when primidone is started, stopped or changed.
Apixaban, dabigatran and rivaroxaban
May reduce anticoagulant exposure and protection against clots; these combinations are not recommended in the selected product information.
Common questions about primidone
Answers are fully visible for fast scanning and source review.
Is primidone used for essential tremor?
Yes. Essential tremor is a licensed indication for the selected product.
Can primidone make you sleepy?
Yes. Sleepiness is particularly common when treatment begins and may impair driving, coordination and reaction time.
Can I drink alcohol while taking primidone?
Sources
These sources were used to prepare and review this medicine page.
Prepared and reviewed by the iatroX editorial team.