Fosphenytoin injection

What is fosphenytoin injection?

FOSPHENYTOIN (Cerebyx®) helps to control seizures (convulsions) in certain types of epilepsy. Fosphenytoin can help to prevent seizures occurring during or after surgery. Generic fosphenytoin injections are not available.

What should I tell my health care provider before I take this medicine?

They need to know if you have any of these conditions:

• an alcohol abuse problem

• blood disorders or disease

• depression

• diabetes

• fever

• heart problems, low blood pressure

• kidney disease

• liver disease

• porphyria

• receiving intramuscular injections

• receiving radiation therapy

• skin problems

• suicidal thoughts, plans, or attempt; a previous suicide attempt by you or a family member

• thyroid disease

• an unusual or allergic reaction to phenytoin, other medicines, foods, dyes, or preservatives

• pregnant or trying to get pregnant

• breast-feeding

How should I use this medicine?

Fosphenytoin is for injection into a vein or muscle or for infusion into a vein. It is given by a health-care professional in a hospital or clinic setting.

What if I miss a dose?

This does not apply. Your condition will be closely monitored to maintain adequate seizure control.

What drug(s) may interact with fosphenytoin?

Many medicines can interact with fosphenytoin; check with your prescriber or health care professional if you regularly take other medications or over-the-counter products. Some of the medicines that can interact with fosphenytoin are listed:

• alcohol

• amphetamines

• aspirin and aspirin-like medicines

• barbiturate medicines for inducing sleep or treating seizures (convulsions)

• bosentan

• carbamazepine

• cimetidine

• ciprofloxacin

• clopidogrel

• cyclosporine

• disulfiram

• ethosuximide

• felbamate

• female hormones, including contraceptive or birth control pills

• fluconazole

• folic acid, vitamin B₉

• heart medicines such as digoxin or digitoxin

• chloramphenicol

• corticosteroid hormones such as prednisone or cortisone

• isoniazid

• itraconazole

• kava kava

• ketoconazole

• leucovorin

• levodopa

• lidocaine

• medicines for diabetes

• medicines for hay fever and other allergies

• medicines for mental depression, anxiety or other mood problems

• medicines to control heart rhythm

• medicines used to treat HIV infection or AIDS

• methadone or other medicines for pain

• methsuximide

• modafinil

• omeprazole

• oxcarbazepine

• rifampin, rifabutin or rifapentine

• sirolimus

• St. John's wort

• tacrolimus

• theophylline

• tiagabine

• ticlopidine

• tramadol

• valproic acid

• voriconazole

• warfarin

• zonisamide

Tell your prescriber or health care professional about all other medicines you are taking, including non-prescription medicines, nutritional supplements, or herbal products. Also tell your prescriber or health care professional if you are a frequent user of drinks with caffeine or alcohol, if you smoke, or if you use illegal drugs. These may affect the way your medicine works. Check with your health care professional before stopping or starting any of your medicines.

What should I watch for while taking fosphenytoin?

Visit your prescriber or health care professional for regular checks on your progress. Your prescriber or health care professional may schedule regular blood tests. Do not stop using fosphenytoin suddenly; this increases the risk of seizures. Because your condition and the use of fosphenytoin carry some risk, it is a good idea to carry an identification card, necklace or bracelet with details of your condition, medications and prescriber or health care professional.

You may feel dizzy or drowsy. Do not drive, use machinery, or do anything that needs mental alertness until you know how fosphenytoin affects you. To reduce the risk of dizzy or fainting spells, do not sit or stand up quickly, especially if you are an older patient. Alcohol can make you more dizzy, increase flushing and may cause rapid heartbeats. Avoid alcoholic drinks while receiving fosphenytoin.

The use of this medicine may increase the chance of suicidal thoughts or actions. Pay special attention to how you are responding while on this medicine. Any worsening of mood, or thoughts of suicide or dying should be reported to your health care professional right away.

Fosphenytoin can cause unusual growth of gum tissues; visit your dentist regularly. Problems can arise if you need dental work, and in the day to day care of your teeth. Try to avoid damage to your teeth and gums when you brush or floss your teeth.

What side effects may I notice from receiving fosphenytoin?

Side effects that you should report to your prescriber or health care professional as soon as possible:

• confusion, nervousness, hostility, or other behavioral changes (especially in children or elderly patients)

• difficulty breathing, wheezing or shortness of breath

• double vision or uncontrollable and rapid eye movement

• fever, sore throat

• headache

• loss of seizure control

• mouth ulcers

• pain, redness, swelling or irritation at the injection site

• poor control of body movements or difficulty walking

• sexual problems (painful erections, loss of sexual desire)

• redness, blistering, peeling or loosening of the skin, including inside the mouth

• skin rash, itching

• stomach pain

• swollen or painful glands

• unusual bleeding or bruising, pinpoint red spots on skin

• unusual tiredness or weakness

• unusual swelling

• worsening of mood, thoughts or actions of suicide or dying

• yellowing of the eyes or skin

Side effects that usually do not require medical attention (report to your prescriber or health care professional if they continue or are bothersome):

• clumsiness or unsteadiness

• constipation

• difficulty sleeping

• dizziness or drowsiness

• dry mouth

• excessive hair growth on the face or body

• nausea, vomiting

• unusual growth of gum tissue

Where can I keep my medicine?

Keep out of the reach of children.

Store in a refrigerator between 2 and 8 degrees C (36 and 46 degrees F); do not freeze. Throw away any unused medicine after the expiration date.