Dilantin

Generic Name: phenytoin (oral) (FEN i toyn)

What is Dilantin?

Dilantin (phenytoin) is an anti-epileptic drug, also called an anticonvulsant. It works by slowing down impulses in the brain that cause seizures.

Dilantin is used to control seizures. It is not made to treat all types of seizures, and your doctor will determine if it is the right medication for you.

Dilantin may also be used for other purposes not listed in this medication guide.

Important information about Dilantin

If you are taking Dilantin to prevent seizures, keep taking the medication even if you feel fine. You may have an increase in seizures if you stop taking Dilantin.

Do not change your dose of Dilantin without your doctor’s advice. Tell your doctor if the medication does not seem to work as well in treating your condition.

You may have thoughts about suicide while taking Dilantin. Your doctor will need to check you at regular visits. Do not miss any scheduled appointments.

Call your doctor at once if you have any new or worsening symptoms while taking Dilantin, such as: mood or behavior changes, depression, anxiety, or if you feel agitated, hostile, restless, hyperactive (mentally or physically), or have thoughts about suicide or hurting yourself.

Before taking Dilantin

You should not use Dilantin if you are allergic to phenytoin.

If you have any of these other conditions, you may need a dose adjustment or special tests to safely use this medication:

liver disease;

porphyria;

diabetes; or

a vitamin D deficiency or any other condition that causes thinning of the bones.

You may have thoughts about suicide while taking Dilantin. Tell your doctor if you have new or worsening depression or suicidal thoughts during the first several months of treatment, or whenever your dose is changed.

Your family or other caregivers should also be alert to changes in your mood or symptoms. Your doctor will need to check you at regular visits. Do not miss any scheduled appointments.

Patients of Asian ancestry may have a higher risk of developing a rare but serious skin reaction to Dilantin. Your doctor may recommend a blood test before you start the medication to determine your risk of this skin reaction.

Dilantin can affect your blood sugar levels. If you are a diabetic, check your blood sugar regularly while you are taking this medication.

FDA pregnancy category D. Dilantin can cause harm to an unborn baby. Dilantin may also not be as effective in reducing seizures if taken during pregnancy. Do not use phenytoin without your doctor’s consent if you are pregnant. Tell your doctor if you become pregnant during treatment. Use an effective form of birth control while you are using this medication.

Dilantin can make birth control pills less effective. Use a non-hormonal form of birth control (such as a condom or diaphragm with spermicide) to prevent an unintended pregnancy.

Phenytoin can pass into breast milk and may harm a nursing baby. Do not use Dilantin without telling your doctor if you are breast-feeding a baby.

How should I take Dilantin?

Take Dilantin exactly as it was prescribed for you. Do not take the medication in larger amounts, or take it for longer than recommended by your doctor. Follow the directions on your prescription label.

Do not crush, chew, break, or open an extended-release capsule. Swallow the pill whole. It is specially made to release medicine slowly in the body. Breaking or opening the pill would cause too much of the drug to be released at one time. Do not use any Dilantin capsule or tablet that has changed colors. Call your doctor for a new prescription.

The chewable tablet may be chewed, broken, or crushed before swallowing, or it may be swallowed whole.

Shake the oral suspension (liquid) well just before you measure a dose. To be sure you get the correct dose, measure the liquid with a marked measuring spoon or medicine cup, not with a regular table spoon. If you do not have a dose-measuring device, ask your pharmacist for one.

To be sure Dilantin is helping your condition, your blood may need to be tested on a regular basis. You may also need a blood test when switching from one form of Dilantin to another. Do not miss any scheduled appointments.

If you are taking Dilantin to treat seizures, keep taking the medication even if you feel fine. You may have an increase in seizures if you stop taking Dilantin. Follow your doctor’s instructions.

Do not change your dose of Dilantin without your doctor’s advice. Tell your doctor if the medication does not seem to work as well in treating your condition.

Carry an ID card or wear a medical alert bracelet stating that you are taking Dilantin, in case of emergency. Any doctor, dentist, or emergency medical care provider who treats you should know that you are taking a seizure medication. Store Dilantin at room temperature away from moisture, light, and heat.

What happens if I miss a dose?

Take the missed dose as soon as you remember. If it is almost time for your next dose, skip the missed dose and take the medicine at your next regularly scheduled time. Do not take extra medicine to make up the missed dose.

What happens if I overdose?

Seek emergency medical attention if you think you have used too much of this medicine. An overdose of Dilantin can be fatal.

Overdose symptoms may include twitching eye movements, slurred speech, loss of balance, tremor, muscle stiffness or weakness, nausea, vomiting, feeling light-headed, fainting, and slow or shallow breathing.

What should I avoid while taking Dilantin?

Avoid drinking alcohol. It can increase some of the side effects of Dilantin, and can also increase your risk of seizure.

Avoid taking antacids at the same time you take Dilantin. Antacids can make it harder for your body to absorb the medication.

Dilantin can cause side effects that may impair your thinking or reactions. Be careful if you drive or do anything that requires you to be awake and alert.

Dilantin side effects

Get emergency medical help if you have any of these signs of an allergic reaction to Dilantin: hives; difficulty breathing; swelling of your face, lips, tongue, or throat.

Call your doctor at once if you have any new or worsening symptoms such as: mood or behavior changes, depression, anxiety, or if you feel agitated, hostile, restless, hyperactive (mentally or physically), or have thoughts about suicide or hurting yourself.

Call your doctor at once if you have any of these serious side effects while using Dilantin:

swollen glands, easy bruising or bleeding;, swollen or tender gums;

fever, sore throat, and headache with a severe blistering, peeling, and red skin rash;

the first sign of any skin rash, no matter how mild;

confusion, hallucinations, unusual thoughts or behavior;

slurred speech, loss of balance or coordination;

tremor (uncontrolled shaking), restless muscle movements in your eyes, tongue, jaw, or neck;

extreme thirst or hunger, urinating more than usual;

loss of appetite, dark urine, clay-colored stools, jaundice (yellowing of the skin or eyes); or

changes in the shape of your face or lips.

Less serious Dilantin side effects may include:

mild skin rash or itching;

dizziness, nervousness, sleep problems (insomnia);

nausea, vomiting, constipation; or

headache, joint pain.

This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

What other drugs will affect Dilantin?

Drugs that can increase Dilantin levels in your blood include:

stomach acid reducers such as cimetidine (Tagamet), ranitidine (Zantac), famotidine (Pepcid), or nizatidine (Axid);

certain sedatives (such as Librium or Valium) or antidepressants (such as Prozac);

estrogen hormone replacement;

chlorpromazine (Thorazine), prochlorperazine (Compazine), thioridazine (Mellaril) and other phenothiazines;

disulfiram (Antabuse);

methylphenidate (Ritalin, Concerta, Daytrana); and

sulfa drugs such as Septra or Bactrim.

Drugs that can make Dilantin less effective in controlling seizures include carbamazepine (Tegretol, Epitol, Carbatrol), sucralfate (Carafate), and molindone (Moban).

Other drugs that can interact with Dilantin include:

phenobarbital (Luminal, Solfoton), valproic acid (Depakene) or divalproex sodium (Depakote);

steroid medicines (prednisone and others);

antidepressants such as amitriptyline (Elavil), clomipramine (Anafranil), imipramine (Janimine, Tofranil), paroxetine (Paxil), and others;

antibiotics such as rifampin (Rimactane, Rifadin, Rifamate) or doxycycline (Doryx, Vibramycin, Adoxa, and others);

digoxin (digitalis, Lanoxin), furosemide (Lasix); and

theophylline (Elixophyllin, Theo-Dur, Theo-Bid, Theolair, Uniphyl).

This list is not complete and there are many other medicines that can interact with Dilantin. Tell your doctor about all the prescription and over-the-counter medications you use. This includes vitamins, minerals, herbal products, and drugs prescribed by other doctors. Do not start using a new medication without telling your doctor. Keep a list with you of all the medicines you use and show this list to any doctor or other healthcare provider who treats you.