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URL of this page: https://medlineplus.gov/druginfo/meds/a682243.html

Clonidine

pronounced as (kloe' ni deen)

Why is this medication prescribed?

Clonidine is used alone or in combination with other medications to treat high blood pressure. Clonidine is also used alone or in combination with other medications as part of a treatment program to control symptoms of attention deficit hyperactivity disorder (ADHD; more difficulty focusing, controlling actions, and remaining still or quiet than other people who are the same age) in children 6 years of age and older. Clonidine is in a class of medications called centrally acting alpha-agonist hypotensive agents. Clonidine treats high blood pressure by decreasing your heart rate and relaxing the blood vessels so that blood can flow more easily through the body. Clonidine extended-release tablets may treat ADHD by affecting the part of the brain that controls attention and impulsivity.

High blood pressure is a common condition and when not treated, can cause damage to the brain, heart, blood vessels, kidneys and other parts of the body. Damage to these organs may cause heart disease, a heart attack, heart failure, stroke, kidney failure, loss of vision, and other problems. In addition to taking medication, making lifestyle changes will also help to control your blood pressure. These changes include eating a diet that is low in fat and salt, maintaining a healthy weight, exercising at least 30 minutes most days, not smoking, and using alcohol in moderation.

How should this medicine be used?

Clonidine comes as a tablet, an extended-release (long-acting) tablet, and an extended-release oral suspension to take by mouth with or without food. The tablet is usually taken two times a day at evenly spaced intervals. If the extended-release tablet is used to treat high blood pressure, it is usually taken once a day. If the extended-release tablet is taken to treat ADHD, it is usually taken once or twice a day. The extended-release oral suspension is usually taken once a day at bedtime. Take clonidine at around the same time(s) every day. Follow the directions on your prescription label carefully, and ask your doctor or pharmacist to explain any part you do not understand. Take clonidine exactly as directed. Do not take more or less of it or take it more often than prescribed by your doctor.

Swallow the extended-release tablets whole; do not split, chew or crush them.

To take the extended-release oral suspension, follow these steps:

  1. Before the first use, uncap the bottle and firmly insert the adapter into the neck of the bottle until the adapter top is even with the bottle top. Do not remove the adapter during the period of time you are using this bottle. Then, replace the cap by turning clockwise.
  2. Shake the bottle gently up and down for at least 10 seconds to mix the medication evenly before each time your take the medication.
  3. To measure your dose, push the plunger of the syringe all the way down and insert the syringe into the adapter of the upright bottle. Then turn the bottle upside down and slowly pull the plunger back to withdraw the amount of suspension prescribed by the doctor. If you are not sure how to correctly measure the dose, ask your doctor or pharmacist. If you see air bubbles in the syringe, push and pull the plunger in and out until the air bubbles are mostly gone. Tap the barrel of the syringe to get rid of any remaining air bubbles.
  4. Remove the syringe from the bottle adapter and slowly squirt the suspension into your mouth or your child's mouth and toward the inside of their cheek. Slowly push the plunger all the way in to give the entire dose. Make sure the child has time to swallow the medication.
  5. Place the bottle cap over the adapter after each use.
  6. Wash the oral syringe after each use by rinsing with water and allow to dry.

Your doctor may start you on a low dose of clonidine and gradually increase your dose, not more than once every week.

Clonidine may help to control your condition but will not cure it. Continue to take clonidine even if you feel well. Do not stop taking clonidine without talking to your doctor. If you suddenly stop taking clonidine, it can cause a rapid rise in your blood pressure and symptoms such as fast heartbeat, nervousness, anxiety, headache, nausea, flushing, lightheadness, chest tightness, and uncontrollable shaking of a part of the body. Your doctor will probably decrease your dose gradually over 2 to days for the regular tablet and 3 to 7 days for the extended-release tablet and oral suspension.

Other uses for this medicine

Clonidine is also used in the treatment of dysmenorrhea (severely painful cramps during menstrual period), hypertensive crisis (a condition in which your blood pressure is very high), menopausal hot flashes, and alcohol and opiate (narcotic) withdrawal. Clonidine is also used and as an aid in smoking cessation therapy and to diagnose pheochromocytoma (a tumor that develops on a gland near the kidneys and may cause high blood pressure and fast heart rate). Talk to your doctor about the possible risks of using this medication for your condition.

This medication may be prescribed for other uses; ask your doctor or pharmacist for more information.

What special precautions should I follow?

Before taking clonidine,

  • tell your doctor and pharmacist if you are allergic to clonidine, any of its ingredients, any other medications, or any of the ingredients in clonidine tablets, extended-release tablets, or extended-release oral suspension. Ask your pharmacist for a list of the ingredients. Also tell your doctor if you have ever had a skin reaction or rash after using clonidine patches.
  • tell your doctor and pharmacist what prescription and nonprescription medications, vitamins, nutritional supplements, and herbal products you are taking or plan to take. Your doctor may need to change the doses of your medications or monitor you carefully for side effects.
  • tell your doctor if you have or have ever had a stroke; low or high blood pressure; a heart attack, an irregular heart beat or heart rhythm problem, or other heart problems; or kidney disease. Also tell your doctor if you have ever fainted.
  • tell your doctor if you are pregnant, plan to become pregnant, or are breast-feeding. If you become pregnant while taking clonidine, call your doctor.
  • if you are having surgery, including dental surgery, tell the doctor or dentist that you are taking clonidine.
  • you should know that clonidine may make you drowsy or dizzy. Do not drive a car or operate machinery until you know how this medication affects you.
  • ask your doctor about the safe use of alcohol while you are taking clonidine. Alcohol can make the side effects from clonidine worse.
  • you should know that clonidine may cause dizziness, lightheadedness, and fainting when you get up too quickly from a lying position. This is more common when you first start taking clonidine. To avoid this problem, get out of bed slowly, resting your feet on the floor for a few minutes before standing up.
  • you should know that clonidine extended-release tablets should be used as part of a total treatment program for ADHD, which may include counseling and special education. Make sure to follow all of your doctor's and therapist's instructions.
  • you should know that you may faint if you become dehydrated or overheated during your treatment with clonidine. Be sure to drink plenty of liquids and stay cool while you are taking this medication.

What special dietary instructions should I follow?

Unless your doctor tells you otherwise, continue your normal diet.

What should I do if I forget a dose?

Take the missed dose as soon as you remember it. However, if it is almost time for the next dose, skip the missed dose and continue your regular dosing schedule. Do not take a double dose to make up for a missed one.

What side effects can this medication cause?

Clonidine may cause side effects. Tell your doctor if any of these symptoms or those listed in the SPECIAL PRECAUTIONS section, are severe or do not go away:

  • dry mouth
  • tiredness
  • weakness
  • headache
  • nervousness
  • decreased sexual ability
  • nausea
  • vomiting
  • constipation

Some side effects can be serious. If you experience any of the following symptoms, call your doctor immediately or get emergency medical treatment:

  • rash
  • hives
  • swelling of the face, throat, tongue, lips, eyes, hands, feet, ankles, or lower legs
  • difficulty swallowing or breathing
  • hoarseness
  • fainting
  • fast or irregular heartbeat

Clonidine may cause other side effects. Call your doctor if you have any unusual problems while taking this medication.

If you experience a serious side effect, you or your doctor may send a report to the Food and Drug Administration's (FDA) MedWatch Adverse Event Reporting program online (https://www.fda.gov/Safety/MedWatch) or by phone (1-800-332-1088).

What should I know about storage and disposal of this medication?

Keep this medication in the container it came in, tightly closed, and out of reach of children. Store it at room temperature and away from light,excess heat and moisture (not in the bathroom). After opening the suspension bottle, discard any unused liquid medication after 60 days.

Unneeded medications should be disposed of in special ways to ensure that pets, children, and other people cannot consume them. However, you should not flush this medication down the toilet. Instead, the best way to dispose of your medication is through a medicine take-back program. Talk to your pharmacist or contact your local garbage/recycling department to learn about take-back programs in your community. See the FDA's Safe Disposal of Medicines website (https://goo.gl/c4Rm4p) for more information if you do not have access to a take-back program.

It is important to keep all medication out of sight and reach of children as many containers (such as weekly pill minders and those for eye drops, creams, patches, and inhalers) are not child-resistant and young children can open them easily. To protect young children from poisoning, always lock safety caps and immediately place the medication in a safe location — one that is up and away and out of their sight and reach. https://www.upandaway.org

In case of emergency/overdose

In case of overdose, call the poison control helpline at 1-800-222-1222. Information is also available online at https://www.poisonhelp.org/help. If the victim has collapsed, had a seizure, has trouble breathing, or can't be awakened, immediately call emergency services at 911.

Symptoms of overdose may include the following:

  • fainting
  • slow heart rate
  • difficulty breathing
  • shivering
  • slurred speech
  • tiredness
  • confusion
  • cold, pale skin
  • drowsiness
  • weakness
  • smaller pupils (black circles in the middle of the eyes)

What other information should I know?

Keep all appointments with your doctor. Your blood pressure should be checked regularly to determine your response to clonidine.

Your doctor may ask you to check your pulse (heart rate) daily and will tell you how rapid it should be. Ask your doctor or pharmacist to teach you how to take your pulse. If your pulse is slower or faster than it should be, call your doctor before taking this medication that day.

To relieve dry mouth caused by clonidine, chew gum or suck sugarless hard candy.

Do not let anyone else take your medication. Ask your pharmacist any questions you have about refilling your prescription.

It is important for you to keep a written list of all of the prescription and nonprescription (over-the-counter) medicines you are taking, as well as any products such as vitamins, minerals, or other dietary supplements. You should bring this list with you each time you visit a doctor or if you are admitted to a hospital. It is also important information to carry with you in case of emergencies.

Brand names

  • Catapres®
  • Jenloga®
  • Kapvay®
  • Nexiclon® XR
  • Onyda® XR

Brand names of combination products

  • Clorpres® (containing Chlorthalidone, Clonidine)
  • Combipres® (containing Chlorthalidone, Clonidine)

This branded product is no longer on the market. Generic alternatives may be available.

Last Revised - 08/20/2024