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What is the most important information I should know about guanabenz?

Do not stop taking guanabenz suddenly without first talking to your doctor. This could cause severely high blood pressure, nervousness, and anxiety. Use caution when driving, operating machinery, or performing other hazardous activities. Guanabenz may cause dizziness or drowsiness. If you experience dizziness or drowsiness, avoid these activities.

Use caution when rising from a sitting or lying position, especially first thing in the morning. Dizziness may occur while taking guanabenz and may result in a fall.

What is guanabenz?

Guanabenz lowers blood pressure by decreasing the levels of certain chemicals in the blood. This allows the blood vessels (veins and arteries) to relax (widen).

Guanabenz is used to treat hypertension (high blood pressure).

Guanabenz may also be used for purposes other than those listed in this medication guide.

What should I discuss with my healthcare provider before taking guanabenz?

Before taking guanabenz, tell your doctor if you have

• heart disease;

• had a heart attack or stroke;

• liver disease; or
• kidney disease.

You may need a dosage adjustment or special monitoring during treatment if you have any of the conditions listed above.

Guanabenz is in the FDA pregnancy category B. This means that it is not expected to be harmful to an unborn baby. Do not take guanabenz without first talking to your doctor if you are pregnant or could become pregnant during treatment. It is not known whether guanabenz passes into breast milk and if it will affect a nursing infant. Do not take guanabenz without first talking to your doctor if you are breast-feeding a baby. If you are over 60 years of age you may be more likely to experience side effects from guanabenz therapy. Your doctor may prescribe a lower dose.

How should I take guanabenz?

Take guanabenz exactly as directed by your doctor. If you do not understand these directions, ask your pharmacist, nurse, or doctor to explain them to you.

Take each dose with a full glass of water.

Take guanabenz at bedtime unless otherwise directed by your doctor. It may cause drowsiness or dizziness. Taking it at bedtime may prevent falls and injuries.

It is important to take guanabenz regularly to get the most benefit.

Do not stop taking guanabenz suddenly without first talking to your doctor. This could cause severely high blood pressure, nervousness, and anxiety.

Your doctor may want you to have blood pressure monitoring or other medical evaluations during treatment with guanabenz to monitor progress and side effects.

Store this medication at room temperature away from moisture and heat.

What happens if I miss a dose?

Take the missed dose as soon as you remember. However, if it is almost time for the next dose, skip the dose you missed and take only the next regularly scheduled dose. Do not take a double dose of this medication.

What happens if I overdose?

Seek emergency medical attention if an overdose is suspected.

Symptoms of a guanabenz overdose include drowsiness, lethargy, weakness, lightheadedness, a slow heart rate, nausea, vomiting, and possibly seizures.