Hydantin
Hydantin is an epilepsy medicine that helps stop seizures from spreading in the brain.
Form
tabletti
Strength
100 mg
Active Ingredient
Phenytoin
Manufacturer
Orion Corporation
How to Use
Dosage
Adults usually start with 200-400 mg per day. Your doctor will tell you the exact dose.
Method
Take this medicine exactly as your doctor tells you. Swallow the tablets whole with a glass of water, either before or after food. If you find it hard to swallow, you can split the tablet at the score line.
Important
Your doctor will decide the highest dose you should take each day. Do not take more than your doctor prescribes.
Possible Side Effects
COMMON
- •Feeling tired, dizzy, shaky, or clumsy
- •Nausea or vomiting
- •Allergic skin rash
- •Increased hair growth
- •Swollen or overgrown gums (can be reduced with good oral hygiene)
- •Uncontrolled eye movements (nystagmus)
- •High liver values or low folate levels (seen in blood tests)
RARE
- •Changes in blood tests, high blood sugar
- •Feeling confused, nerve damage in arms and legs, problems with thinking
- •Heart rhythm problems
- •Soft bones (osteomalacia) or fractures
- •Severe skin reactions, including life-threatening ones like Stevens-Johnson syndrome, toxic epidermal necrolysis, or lupus-like rash.
- •Serious allergic reactions (like anaphylaxis) or a syndrome affecting many organs (hypersensitivity syndrome)
- •Severe drug rash with eosinophilia and systemic symptoms (DRESS syndrome)
- •Liver inflammation or damage
- •Swollen lymph nodes
Important Warnings
- Do not take this medicine if you are allergic to phenytoin or any other ingredient, or if you have porphyria (a rare blood disorder).
- Tell your doctor if you have liver or kidney problems, or if you drink a lot of alcohol, as this can change how the medicine works.
- Some people taking epilepsy medicines, including Hydantin, have had thoughts of harming themselves. If you have such thoughts, contact your doctor right away.
- Stop taking Hydantin and see your doctor right away if you get a skin rash, blisters, or other serious skin reactions (like Stevens-Johnson syndrome or toxic epidermal necrolysis), as these can be dangerous.
- Do not stop taking Hydantin suddenly. Your doctor will gradually lower your dose over several months, because stopping too fast can cause more seizures. Always talk to your doctor before changing your dose or stopping.
Show 1 more warnings
- Talk to your doctor if you are pregnant, breastfeeding, or planning to get pregnant. This medicine can also make you feel sleepy or less alert, so be careful when driving or using machines until you know how it affects you.
Use in Elderly Patients
Category D
Avoid use in older adults. Narrow therapeutic range. Changes in concentration difficult to predict based on dose. Monitor the drug concentration. Consider the numerous potential adverse effects and interactions. (updated 10.11.2025)