Clonidine vs. Klonopin : What Are the Differences?

The Basics of Clonidine & Klonopin

Clonidine is a type of antihypertensive medication, helping to lower blood pressure and heart rate. It is available under several brand names, including Catapres, Catapres-TTS, Duraclon, Jenloga, and Kapvay. It is a short-acting medication, with an elimination half-life between 6 and 20 hours, assuming an individual’s body is healthy and metabolizes normally.

Klonopin is a brand name for the drug clonazepam, a benzodiazepine. It has an elimination half-life of about 20 to 60 hours, classifying it as either a long-acting benzodiazepine or an intermediate-acting, depending on one’s definition.

Despite superficially similar names, these drugs are not in the same class of medication, although they can be used to treat some of the same issues. Note that Klonopin is a brand name, while clonidine is a generic drug name. 

This table can help you understand the basics of both drugs at a glance.

How Do These Drugs Work?

Clonidine acts on alpha-adrenergic and imidazoline receptor agonists, calming the arteries and boosting blood supply to the heart. This results in lowered blood pressure and a slower heart rate.

The hypothalamus and medulla in the brain stem control how hard your heart beats and how tight your blood vessels are. When you’re under pressure, these parts of the brain make your blood vessels squeeze tight and your heart beat faster. Clonidine blocks these signals, calming your overall nervous system.

If you quit clonidine abruptly, you could experience withdrawal symptoms like headache, fast heartbeat, nausea, flushing, lightheadedness, and anxiety.

Clonazepam is a benzodiazepine that acts by enhancing the effect of a neurotransmitter in the brain called γ-aminobutyric acid type A (GABA-A). This causes a sedative-hypnotic effect, which helps to slow abnormal activity in the brain. In the case of Klonopin, the medication can be used to treat panic disorders and some seizure disorders.

Klonopin works directly on GABA, chemical messengers within the brain. With Klonopin, parts of the brain that are overactive are quieter and calmer. As a result, people feel calmer and less anxious.

If you quit Klonopin abruptly, you can experience serious side effects like seizures. Anyone who uses the drug should work with a doctor to taper the dose slowly to allow the brain to adjust.

What Are These Drugs Used For?

The U.S. Food and Drug Administration (FDA) approved clonidine to treat attention deficit hyperactivity disorder (ADHD), Tourette syndrome, and cancer pain. It’s sometimes used off-label to treat the following conditions:

• Sleep issues
• Anxiety
• Post-traumatic stress disorder (PTSD)
• High blood pressure
• Withdrawal symptoms from opioids, benzodiazepines, and alcohol

The FDA-approved Klonopin to treat seizure and panic disorders. It’s sometimes used off label to treat the following conditions:

• Mania
• Restless leg syndrome
• Insomnia
• Sleep disorders
• Alcohol withdrawal

Key Differences Between Klonopin & Clonidine

Because these drugs are in two different classes of medication, they are significantly different in many ways. One of the most significant differences is their mechanism of action.

Fundamentally, clonidine acts in a way that primarily affects the heart, with further effects generally stemming from the changes it causes to a person’s heart rate and blood pressure.

Clonazepam and other benzodiazepines primarily act in such a way that the brain is affected, with further effects stemming from the way it changes brain activity.

Klonopin is a Schedule IV drug, meaning that it has a potential for abuse. Doctors are encouraged to monitor their patients, and they may not provide Klonopin to people with a history of drug abuse. 

Clonidine is different, as it’s not a scheduled drug. It has no known potential for abuse or dependence. This difference in schedule designation means Klonopin has a higher risk of abuse than clonidine.

Is One Drug More Effective?

These drugs don’t share significant enough overlap to claim one is more effective than the other. They act on the body in different ways. With that said, clonidine often won’t be one of the first options a doctor chooses to treat something like severe anxiety, whereas a benzodiazepine might be considered for this purpose. Meanwhile, benzodiazepines cannot directly treat many of the issues clonidine is used to help with, such as hypertension.

Research into some of the off-label uses for clonidine is ongoing, but promising. One of its more interesting potential uses is to treat combat nightmares in patients with post-traumatic stress disorder. It seems to do this effectively enough that it may one day be approved for this kind of use.

Is Either Drug More Addictive?

Klonopin is a Schedule IV substance, the second lowest category. This means it is considered by the DEA to have some abuse potential, but not enough that it is a generally major concern, at least when taken as intended.

Clonidine isn’t scheduled at all. It is generally used to treat hypertension and considered not to have significant abuse potential.

There are rare reports of clonidine abuse, although this abuse seems to be uncommon. Clonidine dependence becomes a bigger concern when mixed with other benzodiazepines, opioids, or alcohol. This is because it can cause a greater level of drowsiness and a high level of detachment from reality, increasing the likelihood that a person may become addicted to its use or otherwise continue to intentionally abuse it.

Benzodiazepines are known to cause physical dependence with long-term use, which is why they’re generally not prescribed for more than a few weeks if alternative options exist. This dependence becomes more likely with long-term or heavy use, with repeated abuse also associated with more intense withdrawal symptoms.

Warnings & Side Effects

Common side effects associated with benzodiazepine use include the following:

• Drowsiness
• Changes in appetite
• Changes in sex drive or ability
• Constipation
• Difficulty concentrating
• Difficulty urinating
• Dizziness
• Dry mouth
• Headache
• Increased salivation
• Irritability
• Joint pain
• Lightheadedness
• Nausea
• Talkativeness
• Tiredness
• Weight changes

The side effects commonly associated with clonidine include the following:

• Abdominal pain
• Constipation
• Diarrhea
• Dizziness
• Dry mouth
• Emotional instability
• Fatigue
• Headache
• Hypotension
• Nausea
• Sedation
• Sexual dysfunction

Side effects often lessen over time, but you should talk to a doctor if any significantly impact your quality of life. You should also talk to your doctor about potentially more serious side effects to watch out for.

If you ever experience a side effect you believe is from your medication, whether it’s on the lists above or not, that seems severe or life-threatening, always call a doctor right away. If it seems like an immediate medical emergency, call 911 instead.

Do not suddenly stop taking Klonopin without first talking to a doctor or you may experience withdrawal. Whether your drug use was prescribed or illicit, a doctor can help you taper your doses so that withdrawal symptoms are minimized, and quitting is easier.

Which Drug Is Better?

Neither drug is better than the other. Neither clonidine or Klonopin is a “perfect” answer to the problems they are often used to treat, and this is because perfect answers generally do not exist in medicine, at least until our understanding of medicine is itself perfect.

They are both valuable tools for doctors to consider when treating patients, with their use backed by evidence and many patients benefiting from them. While both medications have risks and downsides, in most cases, they are prescribed because the benefits outweigh these.