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Guanfacine Hydrochloride Oral tablet

What is this medicine?

GUANFACINE (GWAHN fa seen) is used to treat high blood pressure.

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 suddenly stop taking this medicine. 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.

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:

  • agitation, anxiety, trembling, or shakiness

  • confusion or excessive drowsiness

  • difficulty breathing

  • dizziness or faintness

  • increased sweating

  • increased urine passed

  • irregular, fast or slow heartbeat

  • muscle weakness or pain

  • nausea, vomiting

  • palpitations or chest pain

  • skin rash, itching

  • stomach pain

  • unusual skin rash or reaction

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

  • constipation

  • weakness

What may interact with this medicine?

  • barbiturate medicines for inducing sleep or treating seizures

  • medicines for high blood pressure

  • phenytoin

  • prescription pain medicines

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.

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.

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 or liver disease

  • an unusual or allergic reaction to guanfacine, other medicines, foods, dyes, or preservatives

  • breast-feeding

  • pregnant or trying to get pregnant

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.

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.