Do not take DILANTIN if you:

  • Are allergic to phenytoin or its inactive ingredients or other anticonvulsants such as CEREBYX (fosphenytoin), PEGANONE (ethotoin), or MESANTOIN (mephenytoin)
  • Have had liver problems from taking phenytoin
  • Take delavirdine (a drug which may be prescribed to you when you suffer from an HIV infection) since DILANTIN modifies its effect

Do not stop taking DILANTIN without first talking to your healthcare provider. Stopping DILANTIN suddenly can cause serious problems. Stopping a seizure medicine suddenly in a patient who has epilepsy can cause seizures that will not stop (status epilepticus).

Do not change your dose of DILANTIN without talking to your healthcare provider. Only your doctor can recommend changing your medication. When a change in the dosage form or brand is prescribed, careful monitoring of phenytoin serum levels should be carried out by your doctor.

Like other antiepileptic drugs, DILANTIN may cause suicidal thoughts or actions in a very small number of people, about 1 in 500. Before you take DILANTIN, tell your healthcare provider if you have or have had depression, mood problems, or suicidal thoughts or behavior. Call a healthcare provider right away if you have thoughts about suicide or dying, attempts to commit suicide, new or worse depression, new or worse anxiety, feeling agitated or restless, panic attacks, trouble sleeping (insomnia), new or worse irritability, acting aggressive, being angry, or violent, acting on dangerous impulses, an extreme increase in activity and talking (mania), other unusual changes in behavior or mood.

DILANTIN can cause a type of serious allergic reaction that may affect different parts of the body such as your liver, kidneys, blood, heart, skin, or other parts of your body. These can be very serious and cause death. Call your healthcare provider right away if you have any or all of these symptoms:

  • Fever
  • Rash
  • Swollen lymph glands
  • Bruise easily
  • Vomiting
  • Sore throat
  • Sores in your mouth
  • Swelling, especially of your face, eye, lips, or tongue, or perigenital swelling and swelling of arms and legs
  • Purple or red spots on your skin
  • Yellowing of the skin and the white parts of your eyes (jaundice)
  • Not wanting to eat (anorexia)
  • Nausea
  • Trouble swallowing or breathing
  • Increased infections

If you experience a rash while taking DILANTIN or any of the symptoms listed below, contact your doctor immediately. DILANTIN may cause serious side effects, including:

  • A serious, life-threatening disorder called Stevens-Johnson syndrome and Drug Reaction with Eosinophilia and Systemic Symptoms (DRESS), which can be fatal
  • Softening of your bones (osteopenia, osteoporosis, and osteomalacia). This can cause broken bones
  • High levels of DILANTIN in your blood that could cause confusion also known as delirium, psychosis, or a more serious condition that affects how your brain works (encephalopathy)
  • DILANTIN can cause overgrowth of your gums. Brushing and flossing your teeth and seeing a dentist regularly while taking DILANTIN can help prevent this

You should stop taking DILANTIN and seek immediate medical care if you develop swelling especially in the face, tongue, or upper airway.

DILANTIN may cause problems with your heart, including a slow heartbeat. Let your healthcare provider know right away if you have any of these symptoms: dizziness, tiredness, feeling like your heart is beating slowly or skipping beats, and chest pain.

Before you take DILANTIN, inform your doctor or pharmacist of all the medications you take, including prescription and over-the-counter medicines, and any medical conditions you have, including if you:

  • Have kidney or liver problems as you may show early signs of toxicity. DILANTIN may cause liver damage
  • Have or had porphyria (por-FER-ee-ah). DILANTIN has been associated with harmful effects on blood cells
  • Have or had diabetes. Your blood sugar level can be altered while taking DILANTIN

If you take DILANTIN during pregnancy, your baby is at risk for serious birth defects and bleeding problems right after birth. Your healthcare provider may give you and your baby medicine to prevent this. All women of childbearing age should talk to their healthcare provider about using other possible treatments instead of DILANTIN. Tell your doctor if you are breastfeeding or plan to breastfeed. DILANTIN can pass into breast milk.

Taking DILANTIN with certain other medicines can cause side effects or affect how well they work. Do not start or stop other medicines without talking to your healthcare provider.

Do not drink alcohol while you take DILANTIN without first talking to your healthcare provider. Drinking alcohol while taking DILANTIN may change your blood levels of DILANTIN, which can cause serious problems.

The most common side effects of DILANTIN include irregular movement of the eye, problems with walking and coordination, slurred speech, trouble sleeping, confusion, dizziness, nervousness, tremor, headache, and nausea.

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DILANTIN is a prescription medicine used to treat certain types of seizures called tonic-clonic (grand mal) and psychomotor (temporal lobe) seizures and to prevent and treat seizures that happen during or after brain surgery.

Please see Full Prescribing Information and Medication Guide.