Nexiclon XR, Clonidine ER (24 Hr), Clonidine

Medically reviewed by Amber Watson, PharmD on May 10, 2023
Written by Patricia Weiser, PharmD

Specifically, the Food and Drug Administration (FDA) has approved clonidine to treat:

• high blood pressure in adults
• attention deficit hyperactivity disorder (ADHD) in some children
• severe pain due to cancer in adults and some children

These approved uses differ based on the form of clonidine your doctor prescribes.

This article describes clonidine’s uses and dosage, ways to save on cost, and more. Below you’ll find some coupon options for clonidine.

This article doesn’t provide coupons for all forms of clonidine, only clonidine oral tablets. To find coupons for the other forms of clonidine see the following articles:

• clonidine (solution)
• clonidine (patch)
• clonidine ER

Boxed warning: Risk of serious heart and blood pressure problems with clonidine epidural injection

Clonidine epidural injection has a boxed warning about the risk of serious heart and blood pressure problems in certain people. Boxed warnings are serious warnings from the Food and Drug Administration (FDA).

For details, see the “Interactions and warnings for clonidine” section below.

Clonidine may cause mild or serious side effects in adults and children. More common mild side effects of clonidine and its serious side effects are listed below. This article doesn’t include all possible side effects (also known as adverse effects) of the drug. Side effects can vary based on your age, overall health, and any other medications you take.

To learn more about clonidine’s side effects, see this article or ask your doctor or pharmacist. You can also read the prescribing information* for clonidine.

* To view clonidine’s prescribing information, see the “Article resources” section below.

Mild side effects

More common mild side effects reported with some forms of clonidine are listed below. These side effects may differ based on the form of clonidine you take or use.

This article doesn’t include all possible mild side effects of the drug. To learn more about clonidine’s side effects based on the form, see the prescribing information for clonidine. (To view clonidine’s prescribing information, see the “Article resources” section below.)

With many drugs, mild side effects may go away within a few days or a couple of weeks. If the side effects are bothersome, tell your doctor or pharmacist. They may be able to suggest ways to manage them.

Clonidine oral tablet’s mild side effects include:

• dry mouth
• drowsiness
• dizziness
• constipation
• mild allergic reaction*

Clonidine’s extended release† oral tablet’s mild side effects include:

• drowsiness
• fatigue (low energy)
• irritability‡
• insomnia (trouble sleeping)‡
• nightmares‡
• mild allergic reaction*

* For details about this side effect, see the “Interactions and warnings for clonidine” section below.
† With extended-release tablets, the active drug is released slowly in your body after you take it.
‡ In studies, this side effect was seen in children ages 6 years and older. For details about clonidine’s studies, see its prescribing information in the “Article resources” section below.

Serious side effects

Serious side effects of clonidine are listed below. These side effects may differ based on the form of clonidine you take or use.

This article doesn’t include all possible serious side effects of the drug. To learn more about clonidine’s side effects based on the form, see the prescribing information* for clonidine.

With many drugs, serious side effects are possible but not common. If you have serious side effects from this drug, call your doctor right away. If you’re having severe symptoms or a medical emergency, call 911 or a local emergency number.

In general, clonidine’s serious side effects include:

• changes in your heart rate, including higher or lower heart rate
• very low blood pressure
• serious heart problems, such as heart failure and irregular heart rate or rhythm
• mental health changes, such as new or worsened anxiety, depression, or hallucinations (seeing or hearing things that aren’t real)
• withdrawal side effects, such as rebound hypertension (extreme increases in blood pressure) and others, if you suddenly stop clonidine treatment†
• boxed warning: risk of serious heart and blood pressure problems with clonidine epidural injection‡
• severe allergic reaction‡

* To view clonidine’s prescribing information, see the “Article resources” section below.
† To learn more about this side effect, see “Is clonidine a controlled substance? Is it addictive?” in the “Common questions about clonidine” section below.
‡ For details about this side effect, see the “Interactions and warnings for clonidine” section below.

The Food and Drug Administration (FDA) approves prescription drugs such as clonidine for certain conditions. Approved uses for clonidine are described below. These uses differ based on the form of clonidine prescribed.

Use for ADHD

Doctors may prescribe clonidine extended-release* oral tablet for treating attention deficit hyperactivity disorder (ADHD). It’s used for this purpose in children ages 6 to 17 years. It’s usually prescribed as a long-term treatment.

ADHD is a mental health condition that causes impulsive behaviors and unusual levels of hyperactivity. Children with ADHD often have symptoms that can cause problems at school. Examples include trouble paying attention and sitting still and becoming easily distracted.

Clonidine may be prescribed with or without certain other medications to treat ADHD. These other medications include stimulants, such as methylphenidate (Concerta, Ritalin, others).

* With extended-release tablets, the active drug is released slowly in your body after you take it.

Use for high blood pressure

Doctors may prescribe clonidine oral tablet and transdermal patch* for treating high blood pressure in adults. It’s usually prescribed as a long-term treatment.

With high blood pressure, your blood pressure is higher than average. (Blood pressure is a measurement of how much force your blood exerts on the walls of your blood vessels.) High blood pressure doesn’t usually cause symptoms.

Clonidine may be prescribed with or without other blood pressure medications.

* A transdermal patch is a patch that you apply to your skin. The drug absorbs into your body through your skin.

Use for pain

Doctors may prescribe clonidine epidural injection to treat severe pain due to cancer. This form of clonidine comes as a liquid solution that’s given as an injection into the space outside your spinal cord. It’s used for this purpose in adults and children when other pain medications haven’t helped enough.

Clonidine epidural injection is usually a short-term treatment that’s given in a hospital by your doctor or another healthcare professional.

With pain due to cancer, you may have severe pain that doesn’t go away. The symptoms can vary depending on the type of cancer you have and the areas of your body affected by the disease.

Doctors may not prescribe clonidine epidural injection in certain situations. In fact, this form of the drug has a boxed warning about the risks of heart and blood pressure problems in certain people. For details about this, see the “Interactions and warnings for clonidine” section below.

Below you’ll find answers to a few commonly asked questions about clonidine.

Can clonidine be used for anxiety, sleep, hot flashes, or withdrawal?

Clonidine is sometimes used off-label for anxiety disorders, problems with sleep, or hot flashes. (With off-label use, a drug is prescribed for a condition other than what it’s approved to treat.)

Clonidine may also be prescribed off-label to manage symptoms of withdrawal in people receiving treatment for alcohol use disorder or opioid use disorder. (Withdrawal symptoms can occur when you stop taking a substance your body is dependent on.)

If you’d like to know more about off-label uses of clonidine talk with your doctor. For details about the approved uses of clonidine, see the “Uses of clonidine” section above.

Is clonidine a controlled substance? Is it addictive?

No. Clonidine is not a controlled substance. Controlled substances are prescription drugs or other substances that are regulated by the government due to certain risks, such as misuse and addiction.

Clonidine isn’t expected to cause addiction. (With addiction, a person continues to use a drug or substance despite the harm it’s causing them.)

However, you should not suddenly stop clonidine treatment. Stopping the drug suddenly may cause withdrawal side effects. (Withdrawal symptoms can occur when you stop taking a drug your body is used to having.) These include:

• rebound hypertension (extreme increases in blood pressure)
• headache
• flushing (temporary warmth, redness, or deepening of skin color)
• nervousness
• chest tightness
• anxiety
• tremors (shaking)

Talk with your doctor if you have questions about what to expect with clonidine treatment.

What is clonidine’s half-life? How does the drug work?

Clonidine’s half-life ranges from 12 to 22 hours, depending on the form of the drug you use. (A drug’s half-life is about how long it takes your body to clear half of a dose.)

Clonidine starts working soon after your first dose. It may take a few hours, days, or weeks to notice the full effects from the medication. This depends on the form of the drug and the condition it’s being used to treat.

Clonidine is used to treat high blood pressure, attention deficit hyperactivity disorder (ADHD), and severe pain due to cancer.* The drug works by decreasing the release of chemicals called epinephrine and norepinephrine in your brain.

Typically, these chemicals send signals that increase your heart rate and blood pressure. They also affect many other physical and mental functions, such as attention, behavior, and pain perception. Clonidine causes less of these brain chemicals to be released, resulting in lower blood pressure. The drug can also reduce symptoms of ADHD and relieve pain in certain situations.

If you have questions about how clonidine works to treat your condition, talk with your doctor.

* For details about the uses of clonidine, see the “Uses of clonidine” section above. 

How does clonidine compare with guanfacine?

Clonidine and guanfacine are similar medications. They belong to the same group of drugs called alpha agonists. Both drugs are prescribed for similar uses,* including:

• high blood pressure in adults
• attention deficit hyperactivity disorder (ADHD) in some children

If you have questions about which of these medications may be right for you, talk with your doctor or pharmacist.

* For details about the uses of clonidine, see the “Uses of clonidine” section above. 

Is clonidine a beta-blocker?

No. Clonidine belongs to a group of drugs called alpha agonists. Beta-blockers are a different group of drugs. Examples of beta-blockers include atenolol (Tenormin) and metoprolol (Lopressor, Toprol XL, others).

Similar to beta-blockers, clonidine can be prescribed to treat high blood pressure.* However, taking these drugs together may increase the risk and severity of certain side effects, such as low blood pressure and dizziness.

If your doctor prescribes a beta-blocker in combination with clonidine, it is important to take these medications exactly as your doctor instructs. And if you’d like to stop taking these drugs, especially clonidine, be sure to talk with your doctor first. They’ll advise the safest way to do this.

If you have questions about clonidine and beta-blockers, talk with your doctor or pharmacist.

* For details about the uses of clonidine, see the “Uses of clonidine” section above.

Does clonidine cause weight loss?

Weight loss wasn’t reported as a side effect in studies* of clonidine. But some side effects of clonidine could lead to weight loss in some people. Examples include decreased appetite and nausea.

In studies, weight gain was reported but wasn’t common. This side effect occurred in people who took clonidine together with other medications. So it isn’t entirely clear if clonidine caused this side effect directly.

Talk with your doctor if you experience weight changes during clonidine treatment.

* For details about clonidine’s studies, see its prescribing information in the “Article resources” section below.

The dosage of clonidine your doctor prescribes may vary based on your condition and certain other factors. Talk with your doctor about the dosage that’s right for you.

Taking, applying, or receiving clonidine

Clonidine oral tablet and extended-release oral tablet are swallowed, with or without food. (With extended-release tablets, the active drug is released slowly in your body after you take it.)

Clonidine transdermal patch is used by applying the patch on your skin. You’ll apply the patch to a hairless area of skin on your chest or upper arm.

Your doctor will talk with you about how to use clonidine oral tablets or clonidine transdermal patch. They’ll explain how much to take or apply and how often. Always follow your doctor’s recommendations.

Clonidine liquid solution is given by epidural injection (injection into the space outside your spinal cord). It’s given by your doctor or another healthcare professional in a hospital. If your doctor recommends clonidine epidural injection for you, they’ll explain how the drug will be given to you. They’ll also explain its risks.

Overdose of clonidine

If you take clonidine by mouth or apply it to your skin, you should not take or apply more than your doctor prescribes. For some drugs, doing so may lead to serious side effects or overdose.

If you think you’ve taken or applied too much clonidine, call your doctor or pharmacist right away. Or you could call 800-222-1222 to speak with someone at America’s Poison Centers. You can also use its online resource. If you have concerning symptoms, call 911 or a local emergency number immediately. You can also go to the closest emergency room.

Below, you’ll find information about clonidine’s possible interactions and warnings.

Interactions of clonidine

For some medications, certain things may affect how the drug works. These include getting vaccines, consuming alcohol or certain foods, or taking the drug with other medications. This effect is called a drug interaction.

Before you take or use clonidine, ask your doctor to check for possible interactions. Be sure to tell them about any of the following you take or use:

• prescription medications
• over-the-counter medications
• vitamins, herbs, or supplements

To learn about drug-condition interactions, see the “Warnings for clonidine” section below.

Warnings for clonidine

Clonidine should be used cautiously by certain people.

Clonidine could cause harm to people with certain health conditions. This effect is called a drug-condition interaction. Other factors can also affect whether clonidine is a safe option for you. These warnings may differ based on the form of clonidine you use.

Ask your doctor about specific warnings for clonidine, and be sure to tell your doctor about your:

• current health, including any allergies to medications
• past health conditions or surgeries

Boxed warning: Risk of serious heart and blood pressure problems with clonidine epidural injection

Clonidine epidural injection has a boxed warning about the risk of serious heart and blood pressure problems in certain people. Boxed warnings are serious warnings from the Food and Drug Administration (FDA).

Clonidine epidural injection is used to treat severe pain due to cancer. But it’s not recommended for treating pain in certain people, including those:

• receiving obstetrical care (care during pregnancy and childbirth)
• receiving postpartum care (care provided to someone who has recently given birth), or
• having or recovering from surgery

This is because low blood pressure and slow heart rate may cause certain complications in these situations. These side effects were commonly reported in studies of clonidine epidural injection.

In rare cases, doctors might recommend clonidine epidural injection, but only when the benefits outweigh the risks.

Clonidine epidural injection is given by your doctor or another healthcare professional in a hospital. If you receive this medication, your doctor will monitor your blood pressure and heart rate very closely. They’ll continue to monitor you until they determine that your blood pressure and heart rate are stable.

If you have concerns about this warning, tell your doctor. They’ll discuss with you the potential risks and benefits of this medication to help determine the right treatment plan for you. To learn more, talk with your doctor or pharmacist.

Allergic reaction

Clonidine can cause an allergic reaction in some people. Severe allergic reactions are rare but possible.

If you’ve had an allergic reaction to clonidine or any of its ingredients, your doctor will likely not prescribe clonidine. They can tell you about medications that are safer options for you.

A mild allergic reaction may cause the following symptoms:

• skin rash
• itchiness
• flushing (temporary warmth, redness, or deepening of skin color)

A severe allergic reaction may cause the following symptoms:

• swelling under your skin, usually in your hands, feet, eyelids, or lips
• swelling of your mouth, throat, or tongue, which can cause breathing problems

If you have an allergic reaction to clonidine, call your doctor right away. If you have severe symptoms, call 911 or a local emergency number.

Pregnancy or breastfeeding and clonidine

Information about clonidine and pregnancy and breastfeeding is described below.

Clonidine and pregnancy

There are risks to using clonidine during pregnancy. But there are also risks with having unmanaged health conditions while pregnant. (Keep in mind that clonidine is used for various conditions. For details, see the “Uses of clonidine” section above.)

Clonidine epidural injection has a boxed warning about the risk of serious heart and blood pressure problems in certain people. This includes people receiving obstetrical care (care during pregnancy and childbirth). Boxed warnings are serious warnings from the FDA. (See “Warnings for clonidine” above for more details.)

If you’re planning a pregnancy or can become pregnant, talk with your doctor about treatment options during pregnancy. Together, you can discuss the risks and benefits of your treatment options and decide whether you should use clonidine during pregnancy.

If you become pregnant while taking clonidine extended-release* oral tablet for attention deficit hyperactivity disorder (ADHD), tell your doctor right away. They’ll advise you to stop taking clonidine slowly with the goal of stopping treatment entirely. They may also prescribe a different medication to manage your ADHD during pregnancy.

* With extended-release tablets, the active drug is released slowly in your body after you take it.

Pregnancy registry for ADHD medications

Your doctor may recommend you enroll in a pregnancy registry online or by calling 866-961-2388. The National Pregnancy Registry of ADHD Medications collects information about drug safety during pregnancy. This information helps doctors and patients make informed choices about medication use during pregnancy.

To learn more about the pregnancy registry for clonidine, talk with your doctor.

Clonidine and breastfeeding

It’s not known whether clonidine should be used while breastfeeding. If you’re currently breastfeeding or planning to do so, talk with your doctor before starting this medication.

You may be able to save money on your prescription for clonidine by using our Perks discount coupons. They can be found at the end of this article.

If you have questions about how to pay for clonidine, talk with your doctor or pharmacist. You can also learn more about the cost of clonidine in this article.

Note: Optum Perks coupons cannot be used with insurance copays or benefits.

This article describes clonidine’s uses and dosage, ways to save on cost, and more. Let your doctor know if you have questions about clonidine or would like more details about it.

Here’s a list of some possible questions you may want to ask your doctor:

• I’m an older adult. Is it safe for me to use clonidine?
• Should I check my blood pressure at home while taking this medication? If so, how often?
• Should I continue taking my other medications with clonidine?

• Clonidine HCl injection, solution. (2022). https://nctr-crs.fda.gov/fdalabel/services/spl/set-ids/7daa1996-ea9f-2576-e053-2991aa0a6be5/spl-doc
• Clonidine hydrochloride extended-release tablets, for oral use. (2023). https://nctr-crs.fda.gov/fdalabel/services/spl/set-ids/f34ae077-4ace-4e0a-bc87-d559b1c5bf2f/spl-doc
• Clonidine hydrochloride tablets. (2023). https://nctr-crs.fda.gov/fdalabel/services/spl/set-ids/075b6261-9064-41da-b5e0-0959767e0d9a/spl-doc
• Clonidine transdermal system, USP. (2023). https://nctr-crs.fda.gov/fdalabel/services/spl/set-ids/7adfc439-e6d0-4593-87dd-0eef36d33c6d/spl-doc
• Food and Drug Administration. (2023). Orange Book: Approved drug products with therapeutic equivalence evaluations. https://www.accessdata.fda.gov/scripts/cder/ob/index.cfm
• Yasaei, R., et al. (2022). Clonidine. https://www.ncbi.nlm.nih.gov/books/NBK459124/

Disclaimer: Optum Perks has made every effort to make certain that all information is factually correct, comprehensive, and up to date. However, this article should not be used as a substitute for the knowledge and expertise of a licensed healthcare professional. You should always consult your doctor or another healthcare professional before taking any medication. The drug information contained herein is subject to change and is not intended to cover all possible uses, directions, precautions, warnings, drug interactions, allergic reactions, or adverse effects. The absence of warnings or other information for a given drug does not indicate that the drug or drug combination is safe, effective, or appropriate for all patients or all specific uses.