Guanfacine (By mouth)
GWAHN-fa-seen
Treats high blood pressure and attention deficit hyperactivity disorder (ADHD).
Drug classes
Antihypertensive, Cardiovascular Agent, Central Nervous System Agent (About this – PubMed Health)
Uses
Uses of This Medicine
Guanfacine is used to treat high blood pressure (hypertension). High blood pressure adds to the workload of the heart and arteries. If it continues for a long time, the heart and arteries may not function properly. This can damage the blood vessels of the brain, heart, and kidneys, resulting in a stroke, heart failure, or kidney failure. High blood pressure may also increase the risk of heart attacks. These problems may be less likely to occur if blood pressure is controlled.
Guanfacine works by controlling the nerve impulses along certain nerve pathways. As a result, it relaxes the blood vessels so that blood passes through them more easily. This helps to lower blood pressure.
Guanfacine extended-release tablets are also used alone or together with other medicines to treat attention deficit hyperactivity disorder (ADHD) in children and adolescents. It works in the treatment of ADHD by increasing attention and decreasing restlessness in children and adults who are overactive, cannot concentrate for very long, or are easily distracted and impulsive. This medicine is used as part of a total treatment program that also includes social, educational, and psychological treatment.
This medicine is available only with your doctor’s prescription.
Other uses (PubMed Health)
How To Use
Tablet, Long Acting Tablet
Take your medicine as directed. Your dose may need to be changed several times to find what works best for you.
For patients with high blood pressure: Take the dose at bedtime unless your doctor tells you differently. This may help you avoid being drowsy during the day.
For patients with ADHD: Take the extended-release tablet at the same time each day. It should not be taken with high-fat meals.
Swallow the extended-release tablet whole. Do not crush, break, or chew it.
Read and follow the patient instructions that come with this medicine. Talk to your doctor or pharmacist if you have any questions.
Missed dose: Take a dose as soon as you remember. If it is almost time for your next dose, wait until then and take a regular dose. Do not take extra medicine to make up for a missed dose. Check with your doctor if you miss your dose of the extended-release tablets for 2 or more days in a row.
Store the medicine in a closed container at room temperature, away from heat, moisture, and direct light.
Drugs and Foods to Avoid
Ask your doctor or pharmacist before using any other medicine, including over-the-counter medicines, vitamins, and herbal products.
Some foods and medicines can affect how guanfacine works. Tell your doctor if you are using any of the following:
Carbamazepine, ketoconazole, rifampin Benzodiazepine medicine Medicine to treat seizures A phenothiazine medicine, such as chlorpromazine, perphenazine, promethazine, prochlorperazine, or thioridazineDo not drink alcohol while you are using this medicine.
Tell your doctor if you use anything else that makes you sleepy. Some examples are allergy medicine, narcotic pain medicine, and alcohol.
When Not To Use
This medicine is not right for everyone. Do not use it if you had an allergic reaction to guanfacine.
Warnings
Tell your doctor if you are pregnant or breastfeeding, or if you have kidney disease, liver disease, heart problems, blood vessel disease, low blood pressure, or had a recent heart attack or stroke.
This medicine may cause low blood pressure. This can make you dizzy, drowsy, or lightheaded, especially if you are dehydrated. Do not drive or do anything else that could be dangerous until you know how this medicine affects you. Stand or sit up slowly if you feel lightheaded or dizzy.
Do not stop using this medicine suddenly. Your doctor will need to slowly decrease your dose before you stop it completely.
Tell any doctor or dentist who treats you that you are using this medicine. You may need to stop using this medicine several days before you have surgery or medical tests.
Your doctor will do lab tests at regular visits to check on the effects of this medicine. Keep all appointments. Your doctor will also check your blood pressure and heart rate while you are using this medicine.
Keep all medicine out of the reach of children. Never share your medicine with anyone.
Possible side effects
Summary More details
Call your doctor right away if you notice any of these side effects:
Allergic reaction: Itching or hives, swelling in your face or hands, swelling or tingling in your mouth or throat, chest tightness, trouble breathing
Chest pain, trouble breathing
Fast, slow, or uneven heartbeat
Lightheadedness, dizziness, or fainting
If you notice these less serious side effects, talk with your doctor:
Constipation, stomach pain
Headache, trouble sleeping
Tiredness or weakness
If you notice other side effects that you think are caused by this medicine, tell your doctor.
Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.
More side effects of this drug
Brand names include
Intuniv, Tenex
There may be other brand names for this medicine.