Dilantin

Phenytoin is used to control certain type of seizures, and to treat and prevent seizures that may begin during or after surgery to the brain or nervous system. Phenytoin is in a class of medications called anticonvulsants. It works by decreasing abnormal electrical activity in the brain.

Medications can interact with certain foods. In some cases, this may be harmful and your doctor may advise you to avoid certain foods. In the case of Dilantin, your healthcare provider may recommend you separate your Dilantin dose at least 2 hours from dairy product consumption, as there is a potential food-drug interaction.

Dilantin doses should be administered at least two hours before, or two hours after, an intermittent tube feeding or ingestion of an enteral supplement. If you are receiving continuous enteral feedings, consult with healthcare provider.

Tell your doctor if you are breastfeeding or plan to breastfeed.

Dilantin has been detected in human breast milk. Because of the possibility for adverse reactions in nursing infants from Dilantin, a choice should be made whether to stop nursing or to stop use of this medication. The importance of the drug to the mother should be considered.

In the U.S.

• Dilantin
• Dilantin-125
• Dilantin Infatabs
• Phenytek

In Canada

• Dilantin-30

Available Dosage Forms:

• Suspension
• Tablet, Chewable
• Capsule, Extended Release
• Capsule

Therapeutic Class: Anticonvulsant

Chemical Class: Hydantoin (class)

In deciding to use a medicine, the risks of taking the medicine must be weighed against the good it will do. This is a decision you and your doctor will make. For this medicine, the following should be considered:

Allergies

Tell your doctor if you have ever had any unusual or allergic reaction to this medicine or any other medicines. Also tell your health care professional if you have any other types of allergies, such as to foods, dyes, preservatives, or animals. For non-prescription products, read the label or package ingredients carefully.

Pediatric

Appropriate studies performed to date have not demonstrated pediatric-specific problems that would limit the usefulness of phenytoin in children.

Geriatric

No information is available on the relationship of age to the effects of phenytoin in geriatric patients. However, elderly patients are more likely to have age-related liver, kidney, or heart problems, which may require an adjustment in the dose for patients taking phenytoin.

Breast Feeding

There are no adequate studies in women for determining infant risk when using this medication during breastfeeding. Weigh the potential benefits against the potential risks before taking this medication while breastfeeding.

Interactions with Medicines

Although certain medicines should not be used together at all, in other cases two different medicines may be used together even if an interaction might occur. In these cases, your doctor may want to change the dose, or other precautions may be necessary. When you are taking this medicine, it is especially important that your healthcare professional know if you are taking any of the medicines listed below. The following interactions have been selected on the basis of their potential significance and are not necessarily all-inclusive.

Using this medicine with any of the following medicines is not recommended. Your doctor may decide not to treat you with this medication or change some of the other medicines you take.

• Amifampridine
• Artemether
• Atazanavir
• Boceprevir
• Cobicistat
• Daclatasvir
• Darunavir
• Dasabuvir
• Delamanid
• Delavirdine
• Elbasvir
• Elvitegravir
• Grazoprevir
• Isavuconazonium
• Lurasidone
• Maraviroc
• Ombitasvir
• Paritaprevir
• Piperaquine
• Praziquantel
• Ranolazine
• Rilpivirine
• Ritonavir
• Telaprevir

Using this medicine with any of the following medicines is usually not recommended, but may be required in some cases. If both medicines are prescribed together, your doctor may change the dose or how often you use one or both of the medicines.

• Abiraterone
• Afatinib
• Aluminum Carbonate, Basic
• Aluminum Hydroxide
• Aluminum Phosphate
• Apazone
• Apixaban
• Apremilast
• Aprepitant
• Aripiprazole
• Axitinib
• Beclamide
• Bedaquiline
• Blinatumomab
• Bortezomib
• Bosutinib
• Brexpiprazole
• Brigatinib
• Bupropion
• Cabozantinib
• Calcifediol
• Calcium Carbonate
• Carbamazepine
• Cariprazine
• Ceritinib
• Clarithromycin
• Clozapine
• Cobimetinib
• Crizotinib
• Cyclophosphamide
• Dabigatran Etexilate
• Dasatinib
• Deferasirox
• Deflazacort
• Desogestrel
• Diazepam
• Diazoxide
• Dienogest
• Digoxin
• Dihydroxyaluminum Aminoacetate
• Dihydroxyaluminum Sodium Carbonate
• Dolutegravir
• Doxorubicin
• Doxorubicin Hydrochloride Liposome
• Dronedarone
• Drospirenone
• Eliglustat
• Enzalutamide
• Erlotinib
• Eslicarbazepine Acetate
• Estradiol
• Ethinyl Estradiol
• Ethosuximide
• Ethynodiol
• Etonogestrel
• Etravirine
• Everolimus
• Exemestane
• Ezogabine
• Fentanyl
• Fluvastatin
• Fosaprepitant
• Gefitinib
• Gestodene
• Golimumab
• Guselkumab
• Halothane
• Ibrutinib
• Idelalisib
• Ifosfamide
• Imatinib
• Infliximab
• Irinotecan
• Irinotecan Liposome
• Itraconazole
• Ivabradine
• Ivacaftor
• Ixabepilone
• Ixazomib
• Ketoconazole
• Lapatinib
• Ledipasvir
• Levonorgestrel
• Lidocaine
• Linagliptin
• Lopinavir
• Macitentan
• Magaldrate
• Magnesium Carbonate
• Magnesium Hydroxide
• Magnesium Oxide
• Magnesium Trisilicate
• Manidipine
• Mestranol
• Methadone
• Methotrexate
• Miconazole
• Midostaurin
• Mifepristone
• Naloxegol
• Netupitant
• Nifedipine
• Nilotinib
• Nimodipine
• Nintedanib
• Norethindrone
• Norgestimate
• Norgestrel
• Olaparib
• Orlistat
• Osimertinib
• Oxycodone
• Palbociclib
• Panobinostat
• Pazopanib
• Perampanel
• Pixantrone
• Ponatinib
• Posaconazole
• Quetiapine
• Regorafenib
• Reserpine
• Ribociclib
• Rifampin
• Rivaroxaban
• Rocuronium
• Roflumilast
• Rolapitant
• Romidepsin
• Saquinavir
• Secukinumab
• Sertraline
• Simeprevir
• Sonidegib
• Sorafenib
• St John's Wort
• Sunitinib
• Tacrolimus
• Tamoxifen
• Tasimelteon
• Temsirolimus
• Tenofovir Alafenamide
• Theophylline
• Thiotepa
• Ticagrelor
• Tofacitinib
• Tolvaptan
• Trabectedin
• Ulipristal
• Valbenazine
• Vandetanib
• Velpatasvir
• Vemurafenib
• Venetoclax
• Vilazodone
• Vincristine
• Vincristine Sulfate Liposome
• Vinflunine
• Vorapaxar
• Voriconazole
• Vortioxetine

Using this medicine with any of the following medicines may cause an increased risk of certain side effects, but using both drugs may be the best treatment for you. If both medicines are prescribed together, your doctor may change the dose or how often you use one or both of the medicines.

• Acetaminophen
• Acetazolamide
• Acyclovir
• Amiodarone
• Amitriptyline
• Amprenavir
• Aripiprazole Lauroxil
• Atorvastatin
• Betamethasone
• Bexarotene
• Bleomycin
• Busulfan
• Capecitabine
• Carboplatin
• Caspofungin
• Chloramphenicol
• Cimetidine
• Ciprofloxacin
• Cisplatin
• Clobazam
• Clofazimine
• Clopidogrel
• Colesevelam
• Cortisone
• Cyclosporine
• Dexamethasone
• Dicumarol
• Digitoxin
• Diltiazem
• Disopyramide
• Disulfiram
• Doxepin
• Doxifluridine
• Felbamate
• Fluconazole
• Fludrocortisone
• Fluorouracil
• Fluoxetine
• Fluvoxamine
• Folic Acid
• Fosamprenavir
• Ginkgo
• Imipramine
• Isoniazid
• Levodopa
• Levomethadyl
• Levothyroxine
• Meperidine
• Methoxsalen
• Methsuximide
• Midazolam
• Nafimidone
• Nelfinavir
• Nilutamide
• Nisoldipine
• Ospemifene
• Oxcarbazepine
• Paclitaxel
• Pancuronium
• Paroxetine
• Phenprocoumon
• Piperine
• Prednisolone
• Prednisone
• Progabide
• Quinidine
• Quinine
• Remacemide
• Rifapentine
• Risperidone
• Rufinamide
• Sabeluzole
• Shankhapulshpi
• Simvastatin
• Sirolimus
• Sulfamethizole
• Sulfamethoxazole
• Sulfaphenazole
• Sulthiame
• Tegafur
• Telithromycin
• Tenidap
• Tiagabine
• Ticlopidine
• Ticrynafen
• Tirilazad
• Tizanidine
• Tolbutamide
• Topiramate
• Trazodone
• Triamcinolone
• Trimethoprim
• Tubocurarine
• Valacyclovir
• Valproic Acid
• Vecuronium
• Verapamil
• Vigabatrin
• Viloxazine

Interactions with Food/Tobacco/Alcohol

Certain medicines should not be used at or around the time of eating food or eating certain types of food since interactions may occur. Using alcohol or tobacco with certain medicines may also cause interactions to occur. The following interactions have been selected on the basis of their potential significance and are not necessarily all-inclusive.

Using this medicine with any of the following may cause an increased risk of certain side effects but may be unavoidable in some cases. If used together, your doctor may change the dose or how often you use this medicine, or give you special instructions about the use of food, alcohol, or tobacco.

• Enteral Nutrition
• Ethanol

Other Medical Problems

The presence of other medical problems may affect the use of this medicine. Make sure you tell your doctor if you have any other medical problems, especially:

• Bone problems (eg, osteomalacia, osteoporosis) or
• Depression or mental illness, history of or
• Diabetes or
• Lymphadenopathy (lymph node problems) or
• Porphyria (an enzyme problem) or
• Vitamin D deficiency—Use with caution. May make these conditions worse.

• Hypoalbuminemia (low albumin in the blood) or
• Kidney disease or
• Liver disease—Use with caution. The effects may be increased because of slower removal from the body.

It is very important that your doctor check your progress at regular visits while you or your child are using this medicine to see if it is working properly and to allow for a change in the dose. Blood tests may be needed to check for any unwanted effects.

Using this medicine while you are pregnant can harm your unborn baby. Use an effective form of birth control to keep from getting pregnant. If you think you have become pregnant while using the medicine, tell your doctor right away.

Do not use this medicine if you or your child are also using delavirdine (Rescriptor®). Using these medicines together may cause unwanted effects.

Lymph node problems may occur while using this medicine. Check with your doctor right away if you or your child have swollen, painful, or tender lymph glands in your neck, armpit, or groin.

Do not stop taking this medicine without first checking with your doctor. Your doctor may want you or your child to gradually reduce the amount you are using before stopping completely.

If you or your child develop a skin rash, hives, or any allergic reaction to this medicine, check with your doctor as soon as possible.

Tell your doctor right away if you or your child develop a fever, rash, swollen, painful, or tender lymph glands in the neck, armpit, or groin, unusual bleeding or bruising, or yellow eyes or skin after taking this medicine. These may be symptoms of a serious and life-threatening condition called Drug Reaction with Eosinophilia and Systemic Symptoms (DRESS).

This medicine may cause liver damage. Check with your doctor right away if you have pain or tenderness in the upper stomach, pale stools, dark urine, loss of appetite, nausea, vomiting, or yellow eyes or skin.

Phenytoin can temporarily lower the number of white blood cells in your blood, increasing the chance of getting an infection. It can also lower the number of platelets, which are necessary for proper blood clotting. If this occurs, there are certain precautions you can take, especially when your blood count is low, to reduce the risk of infection or bleeding:

• If you can, avoid people with infections. Check with your doctor immediately if you think you are getting an infection or if you get a fever or chills, cough or hoarseness, lower back or side pain, or painful or difficult urination.
• Check with your doctor immediately if you notice any unusual bleeding or bruising, black, tarry stools, blood in the urine or stools, or pinpoint red spots on your skin.
• Be careful when using a regular toothbrush, dental floss, or toothpick. Your medical doctor, dentist, or nurse may recommend other ways to clean your teeth and gums. Check with your medical doctor before having any dental work done.
• Do not touch your eyes or the inside of your nose unless you have just washed your hands and have not touched anything else in the meantime.
• Be careful not to cut yourself when you are using sharp objects such as a safety razor or fingernail or toenail cutters.
• Avoid contact sports or other situations where bruising or injury could occur.

This medicine may decrease bone mineral density. A low bone mineral density can cause weak bones or osteoporosis. If you or your child have any questions about this ask your doctor.

This medicine may affect blood sugar levels. If you or your child notice a change in the results of your blood or urine sugar tests or if you have any questions, check with your doctor.

This medicine may cause some people to be agitated, irritable, or display other abnormal behaviors. It may also cause some people to have suicidal thoughts and tendencies or to become more depressed. If you, your child, or your caregiver notice any of these side effects, tell your or your child's doctor right away.

In some patients (usually younger patients), tenderness, swelling, or bleeding of the gums (gingival hyperplasia) may appear soon after phenytoin treatment is started. To help prevent this, brush and floss your teeth carefully and regularly and massage your gums. Also, see your dentist every 6 months to have your teeth cleaned. If you have any questions about how to take care of your teeth and gums, or if you notice any tenderness, swelling, or bleeding of your gums, check with your doctor or dentist.

Before you have any medical tests, tell the medical doctor in charge that you or your child are taking this medicine. The results of some tests may be affected by this medicine.

This medicine may cause drowsiness, trouble thinking, or trouble in controlling movements. Make sure you know how you react to this medicine before you drive, use machines, or do other jobs that require you to be alert, well-coordinated, or able to think or see well.

Avoid drinking alcohol while you are taking this medicine.

Do not take other medicines unless they have been discussed with your doctor. This includes prescription or nonprescription (over-the-counter [OTC]) medicines and herbal or vitamin supplements.

Use this medicine as ordered by your doctor. Read all information given to you. Follow all instructions closely.

• Take with or without food. Take with food if it causes an upset stomach.
• Take Dilantin (phenytoin suspension) at the same time of day.
• To gain the most benefit, do not miss doses.
• Keep taking this medicine as you have been told by your doctor or other health care provider, even if you feel well.
• Do not stop taking Dilantin all of a sudden without calling your doctor. You may have a greater risk of seizures. If you need to stop this drug, you will want to slowly stop it as ordered by your doctor.
• Do not take antacids at the same time as this medicine. Ask your doctor if you have a question about how to take antacids with Dilantin.
• If this medicine is given through a feeding tube, stop tube feeding for 2 hours before giving Dilantin. Restart tube feeding 2 hours after giving.
• Shake well before use.
• Measure liquid doses carefully. Use the measuring device that comes with this medicine. If there is none, ask the pharmacist for a device to measure Dilantin.
• This medicine interacts with many other drugs. The chance of this medicine's side effects may be raised or how well Dilantin works may be lowered. The chance of the other drugs' side effects may also be raised. This may include very bad, life-threatening, or deadly side effects. Check with your doctor and pharmacist to make sure that it is safe for you to take this medicine with all of your other drugs (prescription or OTC, natural products, vitamins).
• Tell all of your health care providers that you take Dilantin. This includes your doctors, nurses, pharmacists, and dentists.
• Talk with your doctor before you drink alcohol or use other drugs and natural products that slow your actions.
• Have blood work checked as you have been told by the doctor. Talk with the doctor.
• This medicine may affect certain lab tests. Tell all of your health care providers and lab workers that you take this medicine.
• Wear disease medical alert ID (identification).
• Follow laws about driving with a seizure problem.
• Do not switch brands or types of Dilantin (phenytoin suspension) (like tablets, liquid) unless you talk with the doctor. They may not work the same.
• Take good care of your teeth. See a dentist often.

What do I do if I miss a dose?

• Take a missed dose as soon as you think about it.
• If it is close to the time for your next dose, skip the missed dose and go back to your normal time.
• Do not take 2 doses at the same time or extra doses.

• If your symptoms or health problems do not get better or if they become worse, call your doctor.
• Do not share your drugs with others and do not take anyone else's drugs.
• Keep a list of all your drugs (prescription, natural products, vitamins, OTC) with you. Give this list to your doctor.
• Talk with the doctor before starting any new drug, including prescription or OTC, natural products, or vitamins.
• This medicine comes with an extra patient fact sheet called a Medication Guide. Read it with care. Read it again each time Dilantin is refilled. If you have any questions about this medicine, please talk with the doctor, pharmacist, or other health care provider.
• If you think there has been an overdose, call your poison control center or get medical care right away. Be ready to tell or show what was taken, how much, and when it happened.

This information should not be used to decide whether or not to take Dilantin or any other medicine. Only the healthcare provider has the knowledge and training to decide which medicines are right for a specific patient. 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 Dilantin. This information is not specific medical advice and does not replace information you receive from the healthcare provider. You must talk with the healthcare provider for complete information about the risks and benefits of using this medicine.

Review Date: October 4, 2017

Carcinogenesis, Mutagenesis, Impairment of Fertility

Carcinogenesis [see Warnings and Precautions (5.7)]

In carcinogenicity studies, phenytoin was administered in the diet to mice (10, 25, or 45 mg/kg/day) and rats (25, 50, or 100 mg/kg/day) for 2 years. The incidences of hepatocellular tumors were increased in male and female mice at the highest dose. No increases in tumor incidence were observed in rats. The highest doses tested in these studies were associated with peak serum phenytoin levels below human therapeutic concentrations.

In carcinogenicity studies reported in the literature, phenytoin was administered in the diet for 2 years at doses up to 600 ppm (approximately 90 mg/kg/day) to mice and up to 2400 ppm (approximately 120 mg/kg/day) to rats. The incidences of hepatocellular tumors were increased in female mice at all but the lowest dose tested. No increases in tumor incidence were observed in rats.

Mutagenesis

Phenytoin was negative in the Ames test and in the in vitro clastogenicity assay in Chinese hamster ovary (CHO) cells.

In studies reported in the literature, phenytoin was negative in the in vitro mouse lymphoma assay and the in vivo micronucleus assay in mouse. Phenytoin was clastogenic in the in vitro sister chromatid exchange assay in CHO cells.

Fertility

Phenytoin has not been adequately assessed for effects on male or female fertility.

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. Phenytoin does not treat all types of seizures, and your doctor will determine if it is the right medicine for you.

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

Seek emergency medical attention or call the Poison Help line at 1-800-222-1222. An overdose of phenytoin 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.

Use is not recommended. Excreted into human milk: Yes

-Because of the low levels of this drug in breastmilk, amounts ingested by the infant are small and usually cause no difficulties when used alone except for rare idiosyncratic reactions. Breastfeeding during monotherapy does not appear to adversely affect infant growth or development. -Combination therapy with sedating anticonvulsants or psychotropics may result in infant sedation or withdrawal reactions. -In one case report, maternal phenytoin dosage requirements decreased as breastfeeding was discontinued.