Correspondingly, how long does phenytoin take to work?
It usually takes around 4 weeks for phenytoin to work properly. This is because the dose of phenytoin needs to be increased slowly to prevent side effects. You may still have seizures or pain during this time.
Secondly, what are the side effects of phenytoin?
Side Effects. Headache, nausea, vomiting, constipation, dizziness, feeling of spinning, drowsiness, trouble sleeping, or nervousness may occur. If any of these effects persist or worsen, tell your doctor or pharmacist promptly. Phenytoin may cause swelling and bleeding of the gums.
Phenytoin is used to prevent and control seizures (also called an anticonvulsant or antiepileptic drug). It works by reducing the spread of seizure activity in the brain.