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Cerebyx (Gemeric Fosphenytoin Injection)

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During or after receiving a fosphenytoin injection, you can encounter acute or life-threatening low blood pressure or irregular heartbeats. Inform your doctor if you experience or have ever experienced irregular heartbeat or heart block. You might not be given an injection of fosphenytoin by your doctor. Moreover, let your doctor know whether you now or previously experienced heart failure or low blood pressure. Dizziness, fatigue, an irregular heartbeat, or chest pain are all symptoms that you should report to your doctor right once.

Each fosphenytoin injectable dose is administered in a medical setting, and a doctor or nurse will closely watch you throughout the procedure as well as for 10 to 20 minutes thereafter.

Why is this medication prescribed?

The injection of fosphenytoin is used to treat primary generalized tonic-clonic seizures, also referred to as grand mal seizures because they affect the entire body, as well as to treat and prevent seizures that could start during or after brain or nervous system operations. For those who are unable to take oral phenytoin, fosphenytoin injection may also be used to control specific types of seizures. The drug fosphenytoin belongs to the group of drugs known as anticonvulsants. It functions by reducing the brain’s aberrant electrical activity.

How should this medicine be used?

A doctor or nurse can administer fosphenytoin injection intravenously (into a vein) or intramuscularly (into a muscle) in a medical setting. Fosphenytoin is frequently administered intravenously slowly. Your body’s reaction to the medication will determine how frequently you receive injections of fosphenytoin and how long your treatment will last. How frequently you will receive injections of fosphenytoin will be specified by your doctor.

For a copy of the manufacturer’s information for the patient, ask your pharmacist or doctor.

Other uses for this medicine

Ask your doctor or pharmacist for more details if you believe this drug should be used for something else.

What special precautions should I follow?

Before receiving fosphenytoin injection,

  • If you have any allergies, including to ethotoin (Peganone), phenytoin (Dilantin, Phenytek), other hydantoin drugs, or any of the chemicals in fosphenytoin injection, notify your doctor and pharmacist very away. Get a list of the components from your pharmacist.
  • Informing your physician that you are taking Delavirdine If you are taking this medicine, your doctor generally won’t want you to get a fosphenytoin injection.
  • Inform your doctor and pharmacist about any vitamins, nutritional supplements, herbal items, and prescription and over-the-counter medicines you are now taking or intend to take. Any of the following should be mentioned: Albendazole (Albenza), amiodarone (Nexterone, Pacerone), warfarin (Coumadin, Jantoven), anticoagulants (also known as “blood thinners”), miconazole (Oravig), itraconazole (Onmel, Sporanox, Tolsura), ketoconazole (Nizoral), albendazole (Albenza), posaconazole (Noxafil), and voriconazole; several antiviral medications, including efavirenz (Sustiva, in Atripla), indinavir (Crixivan), lopinavir (in Kaletra), nelfinavir (Viracept), ritonavir (Norvir, in Kaletra), and saquinavir (Invirase); bleomycin; capecitabine (Xeloda); carboplatin; chloramphenicol; drugs for lowering cholesterol such as atorvastatin (Lipitor, in Caduet), fluvastatin (Lescol), and simvastatin (Zocor, in Vytorin); cisplatin; clozapine (Fazaclo, Versacloz); cyclosporine (Gengraf, Neoral, Sandimmune); diazepam (Valium); diazoxide (Proglycem); digoxin (Lanoxin); fluorouracil; fluoxetine (Prozac, Sarafem, in Symbyax, among others); fluvoxamine (Luvox); doxorubicin (Doxil); doxycycline (Acticlate, Doryx, Monodox, Oracea, and Vibramycin); folic acid; fosamprenavir (Lexiva); furosemide (Lasix); and H2 antagonists such as cimetidine, hormonal contraceptives (birth control pills, patches, rings, or injections); hormone replacement treatment (HRT); irinotecan (Camptosar); isoniazid (Laniazid, in Rifamate, in Rifater); famotidine (Pepcid), nizatidine (Axid), and ranitidine (Zantac); medications for nausea and mental illness; additional seizure medications like oxcarbazepine (Trilepta, Oxtellar XR), ethosuximide (Zarontin), felbamate (Felbatol), lamotrigine (Lamictal), methsuximide (Celontin), and phenobarbital; and nifedipine (Adalat, Procardia), nimodiwashpine (Nymalize), nisoldipine (Sular), topiramate (Topamax), and valproic acid (Depakene); methadone (Dolophine, Methadose); methotrexate (Otrexup, Rasuvo, Trexall, Xatmep); methylphenidate (Daytrana, Concerta, Metadate, Ritalin); omeprazole (Prilosec), oral steroids such dexamethasone, methylprednisolone (Medrol), prednisolone, and prednisone (Rayos), paroxetine (Paxil, Pexeva), praziquantel (Biltricide), quetiapine (Seroquel), quinidine (in Nuedexta), reserpine, and rifampin (Rifadin, Rimactane, in Rifamate, in Rifater); aspirin, choline magnesium trisalicylate, choline salicylate, diflunisal, magnesium salicylate (Doan’s, among others), and salsalate are salicylate painkillers. Sertraline (Zoloft), sulfa antibiotics, teniposide, theophylline (Elixophyllin, Theo-24, Theochron), and theophylline are also salicylate painkillers, verapamil (Calan, Verelan, in Tarka), vigabatrin (Sabril), trazodone, tolbutamide, and vitamin D. Your physician might need to adjust the dosage of your drugs or keep a closer eye on you for adverse effects.
  • In particular, mention St. John’s wort to your doctor when you use any herbal remedies.
  • In case you received phenytoin or a fosphenytoin injection in the past and experienced a liver issue, let your doctor know. Most likely, receiving an injection of fosphenytoin is not what your doctor would like.
  • If you consume substantial amounts of alcohol now or have previously done so, let your doctor know. Inform your doctor if you’ve had laboratory work done that revealed you have a hereditary risk factor for developing a severe skin reaction to fosphenytoin. Additionally, let your doctor know if you suffer from or have ever suffered from diabetes, porphyria (a condition in which the body accumulates certain natural substances that can result in stomach pain, mental or behavioral changes, or other symptoms), low albumin levels, or kidney or liver disease.
  • Inform your physician if you are nursing a baby, intend to get pregnant, or are already pregnant. See your doctor about reliable birth control options you can take while undergoing therapy. The fetus may suffer from fosphenytoin.
  • Inform the surgeon or dentist that you are receiving a fosphenytoin injection if you are having surgery, including dental surgery.
  • The safe consumption of alcohol while taking this medicine should be discussed with your doctor.
  • The best strategy to take care of your teeth, gums, and mouth while receiving injections of fosphenytoin should be discussed with your doctor. You must take excellent care of your mouth to reduce the chance that fosphenytoin will harm your gums.

What side effects can this medication cause?

Your blood sugar may rise as a result of fophenytoin. The signs of high blood sugar and what to do if you experience them should be discussed with your doctor.

Side effects from fosphenytoin injection are possible. If any of these symptoms are severe or do not go away, let your doctor know right once:

  • Feeling of tingling, burning, or itching
  • Irregular eye motions
  • Inconsistent body movements
  • Inability to coordinate
  • Confusion
  • Dizziness
  • Weakness
  • Agitation
  • Muddled speech
  • Mouth ache
  • Headache
  • Alterations to your palate
  • Vision issues
  • Hearing loss or ringing in the ears
  • Constipation

Certain adverse effects can be very harmful. Call your doctor right away if you encounter any of the following signs or any of those detailed in the SPECIAL PRECAUTIONS section:

  • Pain, swelling, or a change in color at the injection site
  • Blisters
  • Rash
  • Hives
  • Enlargement of the tongue, throat, cheeks, or eyes
  • Breathing or swallowing challenges
  • Hoarseness
  • Enlarged glands
  • Nausea
  • Vomiting
  • Eyes or skin that have a yellow tint
  • Stomach’s upper right corner hurts
  • Extreme fatigue
  • Significant bruising or bleeding
  • Little skin patches that are red or purple
  • Reduced appetite
  • Flu-like signs
  • Inflammation of the face, a fever, a sore throat, a rash, mouth ulcers, or easy bruising
  • Arms, hands, ankles, or lower legs swelling

Further negative consequences from fosphenytoin injection are possible. If you have any strange side effects while taking this medicine, contact your doctor right once.

You or your doctor can submit a report to the Food and Drug Administration’s (FDA) MedWatch Adverse Event Reporting program online or by phone if you have a serious side event.

Receiving fosphenytoin may raise your risk of developing lymph node issues, such as Hodgkin’s disease. Discuss the dangers of using this drug to treat your disease with your doctor.

In case of emergency/overdose

Call the poison control hotline at 1-800-222-1222 in the event of an overdose. Moreover, information can be found online at Call 911 right once if the person has collapsed, experienced a seizure, is having difficulty breathing, or cannot be roused.

Overdose symptoms could include:

  • Nausea
  • Vomiting
  • Fatigue
  • Fainting
  • Unsteady heartbeat
  • Irregular eye motions
  • Inability to coordinate
  • Slurred or sluggish speech
  • Body part shaking that is uncontrollable

What other information should I know?

Keep all of your appointments with your physician and the lab. To determine how you responded to the injection of fosphenytoin, your doctor can conduct a few lab tests.

Inform the lab staff and your doctor that you are receiving an injection of fosphenytoin prior to any laboratory test.

You should keep a written record of every medication you take, including any over-the-counter (OTC) items, prescription drugs, and dietary supplements like vitamins and minerals. This list should be brought with you whenever you see a doctor or are admitted to the hospital. You should always have this information with you in case of emergencies.

Brand names

  • Cerebyx®
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