Festphenytoin Capsules Capsule (Phenytoin) — Uses, Dosage & NAFDAC

Who is this for?

What is this drug?

Phenytoin is a medicine that calms down abnormal electrical activity in the brain to prevent and control seizures (convulsions). It works by slowing down the nerve signals that cause fits.

What is it used for?

Epilepsy (seizures/convulsions)prevention of seizures after brain surgerystatus epilepticus (prolonged seizures that won't stop)

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Epilepsy & Seizures Nerve Pain

Prescription Required

You need a doctor's prescription to buy this drug.

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How to take this drug

Adults usually start with one 100 mg capsule taken 3 times a day. Your doctor will adjust the dose based on how you respond — some people need up to 300-400 mg daily. Swallow the capsule whole with a full glass of water. You can take it with or after food to reduce stomach upset. Take it at the same times every day and never change your dose without your doctor's approval.

What if I Miss a Dose?

If you miss a dose, take it as soon as you remember. But if it is almost time for your next dose, skip the missed one and continue your normal schedule. Never take two doses at once to make up for a missed one — this can cause dangerous side effects.

What to watch out for

Do not stop taking phenytoin suddenly on your own — stopping abruptly can cause very dangerous non-stop seizures. Always buy from a licensed pharmacy and check the expiry date — avoid buying from roadside vendors or unregistered sellers. Phenytoin requires regular blood tests to make sure the level in your body is safe, so keep your hospital appointments.

Common Side Effects

Feeling dizzy or lightheaded
swollen or overgrown gums (very common with long-term use — brush your teeth regularly)
unsteady walking or poor coordination
feeling sleepy or drowsy
mild skin rash

Serious Side Effects

Severe skin rash with peeling or blisters (this is an emergency — stop the drug and go to the hospital immediately)
signs of liver problems like yellowing of the eyes or skin (jaundice)
severe confusion
slurred speech or difficulty breathing (may mean the drug level is too high in your blood)

Drug Interactions

Alcohol — drinking alcohol while on phenytoin can increase dizziness and make seizures harder to control, so avoid it. Antacids and ulcer drugs (like omeprazole or cimetidine) can change how phenytoin works in your body — space them apart or ask your pharmacist. Some antibiotics and antimalarials can also interact, so always tell your doctor about every medicine you are taking.

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Pregnancy & Breastfeeding Warning

Phenytoin is NOT safe during pregnancy as it can cause serious birth defects; if you are pregnant, planning to become pregnant, or breastfeeding, talk to your doctor immediately about safer alternatives.

Who Should NOT Take This

People who are allergic to phenytoin or similar drugs (like fosphenytoin)
people with certain heart rhythm problems (heart block or very slow heartbeat)
people with severe liver disease
and pregnant women unless the doctor says the benefit outweighs the risk.

How to Store

Store in a cool, dry place away from direct sunlight and heat — Nigerian weather can be very hot, so avoid leaving it in a car or near a window. Keep the container tightly closed to protect from humidity. Always keep out of reach of children.

For information only — not medical advice. Always talk to a doctor or pharmacist before changing your medication.

Festphenytoin Capsules