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 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 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.
Guanabenz Side Effects
What are the possible side effects of Guanabenz?
If you experience any of the following serious side effects, stop taking guanabenz and seek emergency medical attention or contact your doctor immediately:
- an allergic reaction (difficulty breathing; closing of the throat; swelling of the lips, tongue, or face; or hives)
- a very slow heart rate (fewer than 60 beats per minute); or
- unusually high or low blood pressure (fainting, severe headache, flushing)
Other, less serious side effects may be more likely to occur. Continue to take guanabenz and talk to your doctor if you experience any of the following:
- unusual fatigue, dizziness, or tiredness
- headache
- constipation, nausea, vomiting, or diarrhea
- insomnia; or
- dry mouth (sucking on ice chips or sugarless hard candy may relieve this side effect)
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. You may report side effects to FDA at 1-800-FDA-1088.
Guanabenz Interactions
What other drugs affect Guanabenz?
Guanabenz may increase the effects of other drugs that cause drowsiness, including antidepressants, alcohol, antihistamines, pain relievers, anxiety medicines, seizure medicines, and muscle relaxants. Dangerous sedation, dizziness, or drowsiness may occur if guanabenz is taken with any of these medications. Tell your doctor about all medicines that you are taking, and do not take any medicine without first talking to your doctor.
Drugs other than those listed here may also interact with guanabenz or affect your condition. Talk to your doctor and pharmacist before taking any prescription or over-the-counter medicines, including vitamins, minerals, and herbal products.
What should I avoid while taking Guanabenz?
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.
Avoid alcohol while taking guanabenz. It may increase drowsiness an dizziness caused by guanabenz. Use caution even with small amounts of alcohol.
Guanabenz may increase the effects of other drugs that cause drowsiness, including antidepressants, alcohol, antihistamines, pain relievers, anxiety medicines, seizure medicines, and muscle relaxants. Dangerous sedation, dizziness, or drowsiness may occur if guanabenz is taken with any of these medications. Tell your doctor about all medicines that you are taking, and do not take any medicine without first talking to your doctor
Guanabenz Dosage.
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 overdose on Guanabenz?
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.
What happens if I miss a dose of Guanabenz?
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.
Sourced from everydayhealth.com