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Horizant

Generic Name: gabapentin enacarbil
Brand Names: Gralise, Horizant, Neurontin, Gabarone

What is Horizant?

Horizant (gabapentin enacarbil) is a prescription medicine used to treat adults with restless legs syndrome and pain from damaged nerves. It affects chemicals and nerves in the body that are involved in the cause of some types of pain.

Horizant is used in adults to treat nerve pain (postherpetic neuralgia) caused by herpes virus or shingles (herpes zoster).

Horizant is also used to treat restless legs syndrome (RLS).

Use only the brand and form of gabapentin your doctor has prescribed. Check your medicine each time you get a refill to make sure you receive the correct form.

Important information

Some people have thoughts about suicide while taking this medicine. Stay alert to changes in your mood or symptoms. Report any new or worsening symptoms to your doctor.

Do not stop using Horizant suddenly, even if you feel fine.

Before taking this medicine

You should not use Horizant if you are allergic to gabapentin.

To make sure Horizant is safe for you, tell your doctor if you have ever had:

  • kidney disease (or if you are on dialysis);

  • diabetes;

  • depression, a mood disorder, or suicidal thoughts or actions;

  • a seizure (unless you take gabapentin to treat seizures);

  • liver disease;

  • heart disease; or

  • (for patients with RLS) if you are a day sleeper or work a night shift.

Some people have thoughts about suicide while taking this medicine. Your doctor should check your progress at regular visits. Your family or other caregivers should also be alert to changes in your mood or symptoms.

It is not known whether this medicine will harm an unborn baby. Tell your doctor if you are pregnant or plan to become pregnant.

Gabapentin enacarbil can pass into breast milk, but effects on the nursing baby are not known. Tell your doctor if you are breast-feeding.

How should I take Horizant?

Take Horizant exactly as prescribed by your doctor. Follow all directions on your prescription label. Do not take this medicine in larger or smaller amounts or for longer than recommended.

Do not crush, chew, or break an extended-release Horizant tablet. Swallow the tablet whole.

If your doctor changes your brand, strength, or type of gabapentin, your dosage needs may change. Ask your pharmacist if you have any questions about the new kind of gabapentin you receive at the pharmacy.

Do not stop using Horizant suddenly, even if you feel fine. Follow your doctor's instructions about tapering your dose.

This medicine can cause unusual results with certain medical tests. Tell any doctor who treats you that you are using gabapentin enacarbil.

Store Horizant extended-release tablets at room temperature away from light and moisture.

Horizant dosing information

Usual Adult Dose of Horizant for Postherpetic Neuralgia:

The recommended dosage is 600 mg orally 2 times a day. Therapy should be initiated at a dose of 600 mg orally in the morning for 3 days of therapy, then increased to 600 mg 2 times a day (1200 mg/day) on day four.
Gabapentin enacarbil extended release tablets available under the trade name Horizant and gabapentin are not interchangeable.
Use: Postherpetic neuralgia

Usual Adult Dose of Horizant for Restless Legs Syndrome:

600 mg orally once daily with food at about 5 PM. A dose of 1,200 mg once daily provided no additional benefit compared with the 600-mg dose, but caused an increase in adverse reactions.
Use: For the treatment of moderate-to-severe primary Restless Legs Syndrome (RLS) in adults

Dosage Information (comprehensive)

What happens if I miss a dose?

Take the missed dose as soon as you remember. Be sure to take the medicine with food. Skip the missed dose if it is almost time for your next scheduled dose. Do not take extra medicine to make up the missed dose.

What happens if I overdose?

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

What should I avoid while taking Horizant?

Gabapentin may impair your thinking or reactions. Be careful if you drive or do anything that requires you to be alert.

Drinking alcohol with this medicine can cause side effects.

Horizant side effects

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

Seek medical treatment if you have a serious drug reaction that can affect many parts of your body. Symptoms may include: skin rash, fever, swollen glands, flu-like symptoms, muscle aches, severe weakness, unusual bruising, or yellowing of your skin or eyes. This reaction may occur several weeks after you began using Horizant.

Report any new or worsening symptoms to your doctor, such as: mood or behavior changes, anxiety, panic attacks, trouble sleeping, or if you feel impulsive, irritable, agitated, hostile, aggressive, restless, hyperactive (mentally or physically), depressed, or have thoughts about suicide or hurting yourself.

Call your doctor at once if you have:

  • seizures;

  • severe weakness or tiredness;

  • problems with balance or muscle movement;

  • upper stomach pain;

  • chest pain, new or worsening cough with fever, trouble breathing;

  • severe tingling or numbness;

  • rapid eye movement; or

  • kidney problems - little or no urination, painful or difficult urination, swelling in your feet or ankles.

Common Horizant side effects may include:

  • headache, dizziness, drowsiness, tiredness;

  • swelling in your hands or feet;

  • problems with your eyes;

  • coordination problems; or

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.

Side Effects (complete list)

What other drugs will affect Horizant?

Taking Horizant with other drugs that make you sleepy can worsen this effect. Ask your doctor before taking a sleeping pill, narcotic medication, muscle relaxer, or medicine for anxiety, depression, or seizures.

Other drugs may interact with gabapentin enacarbil, including prescription and over-the-counter medicines, vitamins, and herbal products. Tell your doctor about all your current medicines and any medicine you start or stop using.

Where can I get more information?

  • Your pharmacist can provide more information about Horizant.
  • Remember, keep this and all other medicines out of the reach of children, never share your medicines with others, and use Horizant only for the indication prescribed.
  • Disclaimer: Every effort has been made to ensure that the information provided by Cerner Multum, Inc. ('Multum') is accurate, up-to-date, and complete, but no guarantee is made to that effect. Drug information contained herein may be time sensitive. Multum information has been compiled for use by healthcare practitioners and consumers in the United States and therefore Multum does not warrant that uses outside of the United States are appropriate, unless specifically indicated otherwise. Multum's drug information does not endorse drugs, diagnose patients or recommend therapy. Multum's drug information is an informational resource designed to assist licensed healthcare practitioners in caring for their patients and/or to serve consumers viewing this service as a supplement to, and not a substitute for, the expertise, skill, knowledge and judgment of healthcare practitioners. The absence of a warning for a given drug or drug combination in no way should be construed to indicate that the drug or drug combination is safe, effective or appropriate for any given patient. Multum does not assume any responsibility for any aspect of healthcare administered with the aid of information Multum provides. The information contained herein is not intended to cover all possible uses, directions, precautions, warnings, drug interactions, allergic reactions, or adverse effects. If you have questions about the drugs you are taking, check with your doctor, nurse or pharmacist.

Copyright 1996-2017 Cerner Multum, Inc. Version: 14.01.

Date modified: November 15, 2017
Last reviewed: October 10, 2017

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