Clonidine is a medication that people can take in the form of a patch or tablet to help treat attention deficit hyperactivity disorder (ADHD).

People with ADHD may have difficulty controlling impulses, managing energy levels, and maintaining attention. A treatment plan for ADHD will typically involve therapy and medication. Standard medications for ADHD include both stimulant and nonstimulant drugs.

People typically start on stimulant drugs and only switch to nonstimulants if they experience side effects. However, doctors may recommend that individuals with severe symptoms use nonstimulants in combination with stimulants.

Clonidine is a nonstimulant ADHD medication that a doctor may also prescribe to lower blood pressure. Currently, researchers are still unsure exactly how clonidine helps manage ADHD symptoms.

In this article, we discuss clonidine in more detail and consider the benefits and risks of taking this drug to treat ADHD.

An image of clonidine medication, which a doctor may prescribe to treat ADHD.Share on Pinterest
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Clonidine is a type of drug known as an alpha-2 adrenergic agonist. The Food and Drug Administration (FDA) has approved it to treat both high blood pressure and ADHD, but doctors may also prescribe it for other, off-label indications.

The drug received FDA approval for treating ADHD in 2010. Clonidine can help reduce blood pressure by relaxing the arteries, but researchers are still unsure of the exact mechanism by which it treats ADHD.

Doctors classify clonidine as a nonstimulant, making it a second-line ADHD medication. Therefore, they may recommend using clonidine to help treat the symptoms of ADHD in people who do not respond well to or cannot take stimulants. They may also suggest that people with severe symptoms of ADHD take clonidine alongside stimulants.

Medications for ADHD generally fall into two categories: stimulant and nonstimulant drugs.

Stimulant medications act on the central nervous system, increasing the levels of circulating neurotransmitters in the brain. Stimulant medications are standard treatments for people with ADHD because they are effective. They work swiftly and can reduce symptoms in about 70–80% of children with the condition. This category of medications includes:

In contrast, nonstimulant drugs may not act on the central nervous system. They typically take longer to start working, but their effect can last for up to 24 hours. They can also help improve focus and attention while reducing impulsivity in a person with ADHD.

Doctors may recommend nonstimulant drugs in the following situations:

  • when a person does not react well to common stimulant drugs
  • if stimulant drugs do not have the desired effect
  • if a person is unable to take stimulants

In some cases, doctors may recommend both a stimulant drug and a nonstimulant drug to increase the effectiveness of each.

Some nonstimulant drugs include:

Clonidine stimulates alpha-adrenergic receptors in the brain, which lowers the heart rate and relaxes the blood vessels, lowering blood pressure. In people with ADHD, clonidine may affect the part of the brain controlling attention and impulsive behavior, but its exact mechanism is still unknown.

A 2016 review notes that alpha-2 adrenergic receptors in the part of the brain called the prefrontal cortex might help with behaviors of inattentiveness, hyperactivity, and impulsivity. Therefore, engaging these receptors with a drug such as clonidine may lead to a reduction in symptoms relating to these behaviors.

The FDA has approved long-acting clonidine to treat ADHD in people aged 6 years and older.

Doctors will typically not prescribe medications for children below this age bracket, as experts know little about the effects of these drugs in very young children. However, therapeutic options may help very young children with ADHD.

People with ADHD can receive clonidine treatment orally or via a patch.

Oral clonidine is available in immediate-release and extended-release tablets. Doctors typically recommend extended-release, or long-acting, versions of the drug, which break down slowly and deliver the drug to the body throughout the day. Depending on the dose, the person may take clonidine two times each day.

The other delivery option is a transdermal patch. A person can apply a sticky patch containing the drug to the arm, and it slowly delivers the drug through the skin throughout the day. Patches can last much longer than tablets, and a person may only need to change them every week.

The dosage may vary slightly depending on the brand of the medication and the doctor’s recommendations. People should always follow guidance from their doctor.

The label information for Kapvay, which is a branded extended-release form of clonidine, recommends starting with a 0.1-milligram (mg) tablet each day at bedtime.

After a week of this minimum dosage, a person can increase the dosage in increments of 0.1 mg until they have the desired response to the medication. This approach helps a person find the minimum effective dosage, which may prevent or minimize side effects from the medication.

After finding the minimum effective dosage, a doctor may recommend splitting the daily dose into morning and bedtime doses. The bedtime dose should be equal to or higher than the morning dose to avoid tiredness in the daytime, as clonidine can cause drowsiness. So, if the person takes 0.3 mg each day, they would take 0.1 mg in the morning and 0.2 mg near bedtime.

As clonidine is a nonstimulant medication, it can take longer for a person with ADHD to notice the effects than it would with a stimulant. It may take several weeks for a person to see the maximum benefit of clonidine, especially if it takes a week or more to determine the correct dosage initially.

However, once the treatment reaches maximum effectiveness, a person should notice results each day they take clonidine.

Clonidine is not a first-line treatment for ADHD, but doctors may prescribe it when stimulant medications are not effective, or there is a risk of an adverse reaction.

Using clonidine for ADHD may help treat symptoms of hyperactivity and impulsivity. A 2020 article notes that nonstimulants, including clonidine, are both effective and well-tolerated in children and adolescents as a complementary treatment to stimulant drugs. A 2016 review also notes that clonidine may have a synergistic effect with stimulant drugs, increasing their effectiveness.

Clonidine may also be a good option for some people who do not respond well to stimulant medications. It does not have the same effects on the body and will not cause the same side effects, so it may be easier for these individuals to tolerate.

Possible side effects of clonidine include:

Side effects may be more likely in people who are sensitive to the drug or take a higher dosage. Due to the fact that clonidine can lower blood pressure, a person may need to monitor their blood pressure. It is also not advisable for people to stop taking clonidine abruptly. People wishing to stop should discuss this with their doctor and slowly lower the dosage to avoid complications from withdrawal.

Although clonidine was originally a medication to control blood pressure, it may be a useful treatment for managing ADHD symptoms. Doctors classify it as a nonstimulant medication for ADHD. A doctor may recommend clonidine to replace a stimulant drug or advise a person to take it alongside a stimulant.

Researchers are still uncertain exactly how clonidine helps treat ADHD, but it may work by acting on the part of the brain that influences inattentiveness, hyperactivity, and impulsivity. People can work with their doctor to find the correct medication and dosage to help treat their ADHD symptoms.