What is this medicine?
GUANFACINE (GWAHN fa seen) is used to treat high blood pressure.
This medicine may be used for other purposes; ask your health care provider or pharmacist if you have questions.
COMMON BRAND NAME(S): Tenex
What should I tell my health care provider before I take this medicine?
They need to know if you have any of these conditions:
- heart disease or recent heart attack
- kidney disease
- liver disease
- history of stroke
- an unusual or allergic reaction to guanfacine, other medicines, foods, dyes, or preservatives
- pregnant or trying to get pregnant
How should I use this medicine?
Take this medicine by mouth with a glass of water. Follow the directions on the prescription label. Take your doses at regular intervals. Do not take your medicine more often than directed. Do not stop taking except on your doctor's advice. Stopping this medicine too quickly may cause serious side effects or your condition may worsen. You must gradually reduce the dose or you may get a dangerous increase in blood pressure. Ask your doctor or health care professional for advice.
Talk to your pediatrician regarding the use of this medicine in children. Special care may be needed.
Overdosage: If you think you have taken too much of this medicine contact a poison control center or emergency room at once.
NOTE: This medicine is only for you. Do not share this medicine with others.
What if I miss a dose?
If you miss a dose, take it as soon as you can. If it is almost time for your next dose, take only that dose. Do not take double or extra doses.
What may interact with this medicine?
- certain medicines for blood pressure, heart disease, irregular heart beat
- certain medicines for depression, anxiety, or psychotic disturbances
- certain medicines for seizures like carbamazepine, phenobarbital, phenytoin
- certain medicines for sleep
- narcotic medicines for pain
This list may not describe all possible interactions. Give your health care provider a list of all the medicines, herbs, non-prescription drugs, or dietary supplements you use. Also tell them if you smoke, drink alcohol, or use illegal drugs. Some items may interact with your medicine.
What should I watch for while using this medicine?
Visit your doctor or health care professional for regular checks on your progress. Check your heart rate and blood pressure regularly while you are taking this medicine. Ask your doctor or health care professional what your heart rate should be and when you should contact him or her.
You may get drowsy or dizzy. Do not drive, use machinery, or do anything that needs mental alertness until you know how this medicine affects you. To avoid dizzy or fainting spells, do not stand or sit up quickly, especially if you are an older person. Alcohol can make you more drowsy and dizzy. Avoid alcoholic drinks.
Avoid becoming dehydrated or overheated while taking this medicine.
Your mouth may get dry. Chewing sugarless gum or sucking hard candy, and drinking plenty of water may help. Contact your doctor if the problem does not go away or is severe.
Do not treat yourself for coughs, colds or allergies without asking your doctor or health care professional for advice. Some ingredients can increase your blood pressure.
What side effects may I notice from receiving this medicine?
Side effects that you should report to your doctor or health care professional as soon as possible:
- allergic reactions like skin rash, itching or hives, swelling of the face, lips, or tongue
- breathing problems
- changes in vision
- chest pain or chest tightness
- depressed mood
- irregular, fast or slow heartbeat
- redness, blistering, peeling or loosening of the skin, including inside the mouth
- signs and symptoms of low blood pressure like dizziness; feeling faint or lightheaded, falls; unusually weak or tired
- trouble sleeping
Side effects that usually do not require medical attention (report to your doctor or health care professional if they continue or are bothersome):
- change in sex drive or performance
- dry mouth
This list may not describe all possible side effects. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.
Where should I keep my medicine?
Keep out of the reach of children.
Store at room temperature between 15 and 30 degrees C (59 and 86 degrees F). Protect from light. Keep container tightly closed. Throw away any unused medicine after the expiration date.
NOTE: This sheet is a summary. It may not cover all possible information. If you have questions about this medicine, talk to your doctor, pharmacist, or health care provider.
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