Clonidine as a Treatment Option for ADHD

Catapres (clonidine) is a medication that was initially approved to treat high blood pressure. However, because of its calming effects, clonidine is often prescribed to people with attention deficit hyperactivity disorder (ADHD). It can help with symptoms such as hyperactivity, impulsivity, aggression, overarousal, and sleep difficulties.

The Food and Drug Administration (FDA) has approved Kapvay, the extended-release version of clonidine, as a medication for children with ADHD ages six and up. It can be taken alone or along with stimulant medication.

How Clonidine Works

Clonidine prompts your brain to send signals to your blood vessels to relax them, lowering blood pressure. Its exact mechanisms in treating ADHD are not fully understood.

Stimulant vs. Non-Stimulant ADHD Medications

ADHD medications are generally categorized as either stimulants or non-stimulants. Clonidine, which is part of the class of drugs known as centrally acting alpha-agonist hypotensive agents, is considered a non-stimulant treatment for ADHD.

Non-stimulant medications are usually prescribed if a person with ADHD can't tolerate stimulant medication because of severe side effects. Some health conditions also prevent using stimulants, such as certain psychiatric disorders, sleep disorders, cardiovascular disease, or a history of stimulant misuse.

Strattera (atomoxetine), the antidepressant medication Wellbutrin (bupropion), and Qelbree (viloxazine) are examples of other non-stimulant medications. The antihypertensive drug Intuniv (guanfacine) is another.

Pros and Cons of Clonidine for ADHD

Pros

Clonidine offers these benefits, especially for children:

• Can boost the effects of stimulants: Clonidine can be prescribed in addition to a stimulant medication, and it often enhances the effectiveness of the stimulant.
• No appetite effect: Clonidine doesn't increase or decrease appetite. Some other stimulants suppress appetite, which can be a problem for people who are already underweight.
• Effective for kids: A meta-analysis of 73 studies looked at the efficacy of six ADHD medications for kids 6 to 18 years old. Among the three non-stimulants included, clonidine was found to be the most effective and tolerable compared with atomoxetine and extended-release guanfacine. (Wellbutrin was left out because evidence was lacking.)
• Reduces anxiety: People who have ADHD often experience anxiety. Medication from the benzodiazepine family, such as Xanax (alprazolam) or Valium (diazepam), is often prescribed for anxiety. However, these can be habit-forming and negatively affect cognitive functions such as attention. For this reason, clonidine is often prescribed to help people with ADHD who have anxiety.
• Helps with sleep difficulties: Sleep problems are another issue many people with ADHD face. A potentially positive effect of taking clonidine is that it can help improve sleep. In fact, some doctors prescribe a low dose of clonidine off-label (this means using an FDA-approved drug for an unapproved use) to help with sleep.
• Not addictive: While traditional stimulant medications might be avoided because they can be habit-forming, clonidine is not considered to be addictive.
• Reduces blood pressure: If you have ADHD and high blood pressure, clonidine may be a good choice for you because it will also help reduce your blood pressure.
• Can treat tic disorders: If you have both Tourette syndrome or another tic disorder and ADHD, clonidine can help the symptoms of both.

Cons

Clonidine is not suitable for everyone. It has some disadvantages that you should know about if you are considering taking clonidine.

• Doesn't help all ADHD presentations: Clonidine helps with hyperactivity, impulsivity, aggression, overarousal, and sleep difficulties. However, it hasn't been found to be as helpful for inattentive symptoms of ADHD.
• Little research on adults with ADHD: Studies have shown that clonidine can help ADHD symptoms in children and adolescents, but clonidine is not typically prescribed for adult ADHD. This could be because the symptoms that clonidine helps the most, such as aggression, hyperactivity, and impulsivity, often diminish in adulthood.
• Less effective than stimulants: Clonidine isn't as effective as stimulant medications for treating ADHD symptoms. However, its effects are significant enough for the FDA to approve its use for ADHD.
• May cause brain fog: Rather than increasing the ability to focus, some people find clonidine reduces their focus or causes brain fog. Problems with the ability to focus can be temporary as your body adjusts to the clonidine. However, some people find this problem continues.
• May cause drowsiness: While clonidine can help with nighttime sleep problems, some people who take clonidine also feel fatigued or sedated during the daytime. This can have negative effects on school or work performance. Sometimes, the sleepiness decreases with time. This is an important side effect to discuss with your doctor, as it has the potential to be dangerous if you drive a vehicle or operate machinery.
• May cause erectile dysfunction (ED): A drawback for men taking clonidine is ED. Even though you might feel embarrassed to talk to your doctor about ED, they will be aware that this is a possible side effect and will want to help you resolve the issue.

Forms and Dosage

When clonidine is first prescribed, it's usually at the lowest dose. This may be 0.05 to 0.1 milligrams (mg) to start. Your doctor gradually increases the dose until the effective (therapeutic) dose is found. Catapres tablets come in 0.1mg, 0.2mg, and 0.3mg. Kapvay is the extended-release version, and it's available in 0.1mg.

Once the therapeutic dose has been found using tablets, using a clonidine patch is an option. It may take a few weeks to see the full effects of clonidine on ADHD symptoms, but you may see some improvement sooner.

Side Effects of Clonidine

These side effects often go away after you've taken the medication for a while, but if they don't or they're bothersome, talk to your doctor:

• Behavior problems
• Constipation
• Dizziness
• Dry mouth
• Erectile dysfunction
• Fatigue
• Headache
• Irritability
• Low blood pressure
• Nausea
• Upper abdominal pain
• Vomiting

Rare But Serious Side Effects

If you experience these or any other unusual or persistent side effects, contact your doctor as soon as possible:

• Difficulty breathing
• Hallucinations
• Hives
• Hoarseness
• Irregular heartbeat
• Rash
• Slow heart rate
• Swelling anywhere in the body

Precautions When Taking Clonidine

If you have a history of low blood pressure, you may be more likely to feel dizzy, lightheaded, and nauseous while taking clonidine.

Many people forget to take their medication. If you miss a dose of clonidine, don't take a double dose as it could lower your blood pressure too much.

It's important that you don't stop taking clonidine abruptly, as this may cause rebound high blood pressure. Instead, your dose should be decreased gradually. Your doctor can give you advice on the best tapering schedule.