Phenytoin immediate-release capsulesPronunciation
Generic Name: phenytoin (FEN-i-toyn)
Brand Name: Generic only. No brands available.
Phenytoin immediate-release capsules is used for:
Treating tonic-clonic (grand mal) and partial seizures. It is also used to prevent and treat seizures that may occur during or after brain or nervous system surgery. It may also be used for other conditions as determined by your doctor.
Phenytoin immediate-release capsules is an anticonvulsant. It works in the brain to block the spread of seizure activity.
Do NOT use phenytoin immediate-release capsules if:
- you are allergic to any ingredient in phenytoin immediate-release capsules or to another hydantoin (eg, fosphenytoin)
- you are taking cabazitaxel, crizotinib, delavirdine, dronedarone, etravirine, lurasidone, nifedipine, nisoldipine, praziquantel, ranolazine, rilpivirine, rivaroxaban, roflumilast, ticagrelor, or vandetanib
Contact your doctor or health care provider right away if any of these apply to you.
Before using phenytoin immediate-release capsules:
Some medical conditions may interact with phenytoin immediate-release capsules. Tell your doctor or pharmacist if you have any medical conditions, especially if any of the following apply to you:
- if you are pregnant, planning to become pregnant, or are breast-feeding
- if you are taking any prescription or nonprescription medicine, herbal preparation, or dietary supplement
- if you have allergies to medicines, foods, or other substances
- if you or a family member have had an allergic reaction to a barbiturate (eg, phenobarbital), carbamazepine, an oxazolidinedione (eg, trimethadione), oxcarbazepine, or a succinimide (eg, ethosuximide, methsuximide)
- if you have the blood disease porphyria, liver disease, diabetes, weakened immune system, bone problems (eg, weak bones, osteoporosis), or a history of lymph gland problems
- if you or a family member has had anticonvulsant hypersensitivity syndrome (AHS)
- if you are in very poor health or you receive nutrition through an enteral tube (eg, G-tube)
- if you drink alcohol or have a history of alcohol abuse
- if you have been tested and know whether or not you have a gene type called HLA-B*1502
- if you have a history of mental or mood problems (eg, depression), or suicidal thoughts or attempts
Some MEDICINES MAY INTERACT with phenytoin immediate-release capsules. Tell your health care provider if you are taking any other medicines, especially any of the following:
- Many other prescription and nonprescription medicines (eg, used for allergic reactions, asthma or other breathing problems, blood thinning, diabetes, infections, inflammation, aches and pains, attention deficit hyperactivity disorder, alcoholism, cancer, high blood pressure, indigestion, irregular heartbeat or other heart problems, hepatitis C, high blood iron levels, high cholesterol, HIV, birth control, hormone replacement, immune system suppression, mental or mood problems, pain, sleep, seizures, stomach or bowel problems), multivitamin products, and herbal or dietary supplements (eg, herbal teas, coenzyme Q10, garlic, ginseng, ginkgo, St. John's wort) may interact with phenytoin immediate-release capsules. Ask your doctor or pharmacist if you are unsure if any of your medicines might interact with phenytoin immediate-release capsules
This may not be a complete list of all interactions that may occur. Ask your health care provider if phenytoin immediate-release capsules may interact with other medicines that you take. Check with your health care provider before you start, stop, or change the dose of any medicine.
How to use phenytoin immediate-release capsules:
Use phenytoin immediate-release capsules as directed by your doctor. Check the label on the medicine for exact dosing instructions.
- Take phenytoin immediate-release capsules by mouth with or without food. If stomach upset occurs, take with food to reduce stomach irritation.
- If you take a calcium product (eg, certain antacids), colesevelam, or molindone, ask your doctor or pharmacist how to take it with phenytoin immediate-release capsules.
- Do not suddenly stop taking phenytoin immediate-release capsules. You may have an increased risk of seizures if you stop taking it. If you need to stop phenytoin immediate-release capsules, your doctor will gradually lower your dose.
- Continue to take phenytoin immediate-release capsules even if you feel well. Do not miss any doses.
- Taking phenytoin immediate-release capsules at the same time each day will help you remember to take it.
- If you miss a dose of phenytoin immediate-release capsules, take it as soon as possible. If it is almost time for your next dose, skip the missed dose and go back to your regular dosing schedule. Do not take 2 doses at once.
Ask your health care provider any questions you may have about how to use phenytoin immediate-release capsules.
Important safety information:
- Phenytoin immediate-release capsules may cause dizziness or drowsiness. These effects may be worse if you take it with alcohol or certain medicines. Use phenytoin immediate-release capsules with caution. Do not drive or perform other possibly unsafe tasks until you know how you react to it.
- Check with your doctor before you drink alcohol while you are taking phenytoin immediate-release capsules. Alcohol may increase or decrease the amount of medicine in your blood.
- Do not change brands or doseforms (eg, tablets, suspension, injection) of phenytoin immediate-release capsules without talking with your doctor.
- Do NOT take more than the recommended dose or change your dose without checking with your doctor.
- Patients who take phenytoin immediate-release capsules may be at increased risk of suicidal thoughts or actions. The risk may be greater in patients who have had suicidal thoughts or actions in the past. Watch patients who take phenytoin immediate-release capsules closely. Contact the doctor at once if new, worsened, or sudden symptoms such as depressed mood; anxious, restless, or irritable behavior; panic attacks; or any unusual change in mood or behavior occur. Contact the doctor right away if any signs of suicidal thoughts or actions occur.
- Proper dental care is important while you are taking phenytoin immediate-release capsules. Brush and floss your teeth and visit the dentist regularly.
- Phenytoin immediate-release capsules may raise your blood sugar. High blood sugar may make you feel confused, drowsy, or thirsty. It can also make you flush, breathe faster, or have a fruit-like breath odor. If these symptoms occur, tell your doctor right away.
- There have been reports of lymph node problems, including cancer, in patients who take phenytoin immediate-release capsules. It is not known if phenytoin immediate-release capsules may be the cause. Contact your doctor right away if you develop swollen lymph nodes.
- A serious and sometimes fatal reaction has been reported in patients taking medicines for seizures, including phenytoin immediate-release capsules. Contact your doctor right away if you develop swollen lymph nodes, fever, rash, chest pain, symptoms of kidney problems (eg, decreased urination), or symptoms of liver problems (eg, dark urine, loss of appetite, pale stools, stomach pain, yellowing of the skin or eyes).
- Long-term treatment with phenytoin immediate-release capsules may cause low blood vitamin D levels. This may increase the risk of low blood calcium or phosphate levels. It may also increase the risk of bone softening, weak bones, or other bone problems (eg, fractures). Discuss any questions or concerns with your doctor.
- Tell your doctor or dentist that you take phenytoin immediate-release capsules before you receive any medical or dental care, emergency care, or surgery.
- Hormonal birth control (eg, birth control pills) may not work as well while you are using phenytoin immediate-release capsules. To prevent pregnancy, use an extra form of birth control (eg, condoms).
- Serious and sometimes fatal skin reactions have been reported with phenytoin immediate-release capsules. Patients who have a certain gene type called HLA-B*1502 may have an increased risk for these skin reactions. This gene type is found most commonly in Asian patients. Tell your doctor if you have been tested and know whether or not you have the HLA-B*1502 gene type. Discuss any questions or concerns with your doctor.
- Phenytoin immediate-release capsules may interfere with certain lab tests. Be sure your doctor and lab personnel know you are taking phenytoin immediate-release capsules.
- Lab tests, including blood phenytoin levels or liver function, may be performed while you use phenytoin immediate-release capsules. These tests may be used to monitor your condition or check for side effects. Be sure to keep all doctor and lab appointments.
- Use phenytoin immediate-release capsules with caution in the ELDERLY; they may be more sensitive to its effects.
- Women who take phenytoin immediate-release capsules may experience an increase in seizure activity if they become pregnant. Discuss any questions or concerns with your doctor. If you think you may be pregnant, contact your doctor.
- Phenytoin immediate-release capsules may cause harm to the fetus. If you may become pregnant, discuss other possible treatment options with your doctor. If a decision is made to take phenytoin immediate-release capsules, use effective birth control while you are taking it. Talk with your doctor if you are planning to become pregnant, or if you have questions or concerns about this information.
- PREGNANCY and BREAST-FEEDING: Phenytoin immediate-release capsules may cause harm to the fetus. If you think you may be pregnant, contact your doctor right away. You will need to discuss the benefits and risks of taking phenytoin immediate-release capsules while you are pregnant. You and your doctor will need to decide if you will continue to take phenytoin immediate-release capsules while you are pregnant. Phenytoin immediate-release capsules is found in breast milk. Do not breast-feed while taking phenytoin immediate-release capsules.
Possible side effects of phenytoin immediate-release capsules:
All medicines may cause side effects, but many people have no, or minor, side effects. Check with your doctor if any of these most COMMON side effects persist or become bothersome:
Seek medical attention right away if any of these SEVERE side effects occur:
Constipation; dizziness; drowsiness; headache; mild nervousness; nausea; trouble sleeping; vomiting.
Severe allergic reactions (rash; hives; itching; difficulty breathing or swallowing; tightness in the chest; swelling of the mouth, eyes, face, lips, or tongue); bone pain; burning, numbness, or tingling; butterfly-shaped rash on the face; chest pain; clumsiness or unsteadiness; confusion; delirium; new or worsening mental or mood changes (eg, agitation, anxiety, behavior changes, depression, irritability, panic attacks, restlessness, suicidal thoughts or attempts); new or worsening seizures; red, swollen, blistered, or peeling skin; severe muscle pain; severe or persistent trouble sleeping; signs of infection (eg, chills, fever, sore throat); slurred speech; sores in the mouth or around the eyes; swollen lymph nodes; swollen or tender gums; symptoms of liver problems (eg, dark urine, loss of appetite, pale stools, stomach pain, yellowing of the skin or eyes); tremor; trouble walking; unusual bruising or bleeding; unusual eye movements; unusual muscle movements; unusual tiredness or weakness.
This is not a complete list of all side effects that may occur. If you have questions about side effects, contact your health care provider. Call your doctor for medical advice about side effects. To report side effects to the appropriate agency, please read the Guide to Reporting Problems to FDA.
If OVERDOSE is suspected:
Contact 1-800-222-1222 (the American Association of Poison Control Centers), your local poison control center, or emergency room immediately. Symptoms may include confusion; decreased coordination; fainting; loss of consciousness; severe dizziness or drowsiness; severe or persistent nausea or vomiting; slow or difficult breathing; sluggishness; speech problems (eg, slurred speech); tremor; unusual eye movements.Proper storage of phenytoin immediate-release capsules:
Store phenytoin immediate-release capsules at room temperature, between 59 and 86 degrees F (15 and 30 degrees C). Store away from heat, moisture, and light. Do not store in the bathroom. Keep phenytoin immediate-release capsules out of the reach of children and away from pets.
- If you have any questions about phenytoin immediate-release capsules, please talk with your doctor, pharmacist, or other health care provider.
- Phenytoin immediate-release capsules is to be used only by the patient for whom it is prescribed. Do not share it with other people.
- If your symptoms do not improve or if they become worse, check with your doctor.
- Check with your pharmacist about how to dispose of unused medicine.
This information is a summary only. It does not contain all information about phenytoin immediate-release capsules. If you have questions about the medicine you are taking or would like more information, check with your doctor, pharmacist, or other health care provider.
Disclaimer: This information should not be used to decide whether or not to take this medicine or any other medicine. Only your health care provider has the knowledge and training to decide which medicines are right for you. This information does not endorse any medicine as safe, effective, or approved for treating any patient or health condition. This is only a brief summary of general information about this medicine. It does NOT include all information about the possible uses, directions, warnings, precautions, interactions, adverse effects, or risks that may apply to this medicine. This information is not specific medical advice and does not replace information you receive from your health care provider. You must talk with your healthcare provider for complete information about the risks and benefits of using this medicine.