Alprazolam (Xanax) and clonazepam (Klonopin) are both medications that affect a person’s central nervous system (CNS) by slowing it down. They are both benzodiazepines but work in different ways.

The most common use of Xanax is as an antianxiety medication. Pharmaceutical company Upjohn created this drug in 1969, and doctors now write more than 50 million prescriptions for Xanax each year.

Clonazepam can help treat seizure disorders, among other things. It is an anticonvulsant and antiepileptic medication. Doctors may also prescribe clonazepam for panic disorder.

Xanax and clonazepam both affect the CNS and have the potential for misuse, with some people becoming dependent on them.

Xanax is a useful medication for people who experience panic attacks. The drug helps relieve the symptoms and reduce the frequency of attacks.

Some doctors prescribe Xanax for depression, but there is limited evidence to suggest that it is effective unless the person also has anxiety.

Clonazepam is also a benzodiazepine. Doctors use it to treat seizure disorders in both adults and children. It can help address chemical imbalances in the brain and reduce the number of panic attacks.

Taking clonazepam increases a person’s levels of gamma-aminobutyric acid (GABA), which is a chemical that sends signals around the CNS.

A lack of GABA activity can cause people to become excitable and may lead to panic attacks or seizures. Having more GABA activity in the body helps reduce instances of panic attacks and seizures.

At first glance, Xanax and clonazepam are very similar. Both medications are benzodiazepines, CNS depressants, and ways of treating anxiety or panic attacks.

Both are short acting drugs, but clonazepam stays in the body for longer than Xanax. The half-life of Xanax is 6–25 hours, while for clonazepam, it is 22–54 hours.

Clonazepam can also treat seizures, whereas Xanax does not. Both drugs have their different off-label uses, which the sections below will look at in more detail.

Dosages usually differ depending on the individual and the condition that a doctor is trying to treat.

Clonazepam dosage

For panic and anxiety, the dosage for adults is 0.25 milligrams (mg) twice per day.

A doctor can increase the dosage in increments of 0.125 mg to 0.25 mg every 3 days until the panic is under control. However, the maximum dosage does not usually exceed 4 mg per day.

For seizures, the dosage for adults is 0.5 mg three times per day. A doctor can increase the dosage in increments of 0.5 mg to 1 mg until the seizures are under control. The maximum dosage should not exceed 20 mg per day.

Xanax dosage

For anxiety disorders, the dosage for adults typically starts at 0.25 mg to 0.5 mg three times per day. A doctor may incrementally increase the dosage to maximize the effect. However, the maximum dosage does not usually exceed 4 mg per day.

For panic disorders, the required dose of Xanax may exceed 4 mg per day.

Controlled trials involving 1,700 people found that Xanax worked for panic disorder when participants received 1–10 mg per day.

Changing dosage

Whether prescribing clonazepam or Xanax, a doctor will usually start at the lowest possible dosage, regularly reassess the dosage, and consider reducing it, for example, if panic attacks stop.

If a doctor advises reducing the dosage, they must ensure that a person does this slowly. If a person stops taking either drug abruptly, it could result in withdrawal symptoms.

Both Xanax and clonazepam typically begin taking effect after a few hours or days of starting the medication.

A dose of Xanax will affect a person for a few hours. A dose of clonazepam can last around three times longer.

Benzodiazepine dependence

Long-term use of benzodiazepines can lead to dependence on these drugs. Dependence can begin after using the drugs for as little as 1 month.

As Xanax remains in the body for less time than clonazepam, it may carry a higher risk of overuse or misuse, which may lead to dependence.

It is critical that a person does not stop taking either drug suddenly. Doing so can lead to adverse effects, such as life threatening seizures, as well as withdrawal symptoms.

A doctor or pharmacist should carefully monitor how a person uses benzodiazepines to manage the risk of dependence.

Clonazepam comes in the form of an oral tablet that a person swallows. There is also a version that dissolves in the mouth.

Xanax is available in immediate-release and extended-release oral tablets, as well as an oral solution.

These drugs can have a number of adverse effects. The sections below will look at these in more detail.


Some of the more common side effects of clonazepam include:

If any of these side effects develop, a person should talk to their doctor.

Some rarer and more severe side effects of clonazepam include:

  • depressed mood or suicidal thoughts
  • seizures, especially if a person stops taking the drug suddenly
  • hallucinations
  • mood and behavioral changes
  • sweating
  • abnormal eye movements
  • anxiety
  • difficulty speaking
  • insomnia
  • excessive bleeding and bruising, from reduced platelets in the blood
  • menstrual problems
  • difficulty urinating

If any of these side effects develop, a person needs immediate medical attention.


Some of the more common side effects of Xanax include:

  • drowsiness and fatigue
  • lightheadedness
  • headaches
  • nausea
  • dry mouth
  • irritability
  • becoming talkative
  • forgetfulness or difficulty concentrating
  • difficulty passing urine
  • constipation
  • joint pain
  • changes in appetite
  • changes in weight
  • sexual dysfunction

If any of these side effects develop, a person should make an appointment to see their doctor.

Some rarer and more severe side effects of Xanax include:

  • yellowing of the skin or eyes
  • difficulty speaking
  • poor coordination and balance
  • seizures
  • mood changes
  • hallucinations
  • confusion or memory problems
  • depression or suicidal thoughts
  • a severe rash

If any of these side effects develop, a person needs immediate medical attention.

As both Xanax and clonazepam may cause drowsiness and poor coordination, people taking these drugs should be cautious about driving and operating machinery.

With either drug, a severe allergic reaction is unlikely. However, if a person develops any symptoms of a reaction — such as a rash, difficulty breathing, itching, or swelling — they need emergency help.

People taking Xanax or clonazepam should not mix them with alcohol or opioid medication. Doing so can cause dangerous side effects that could be fatal.

Other CNS depressants can also interact with Xanax or clonazepam and change the way they work. Such changes can also lead to severe side effects.

Some other CNS depressants include:

  • cannabis
  • antihistamines
  • sedatives and sleeping pills
  • tranquilizers
  • mood stabilizers
  • muscle relaxants
  • seizure medications
  • pain medications

Before starting to take a new medication, a person should tell their doctor or pharmacist about any other drugs that they are taking or planning to take.

Off-label uses are uses that are not indicated on the Food and Drug Administration (FDA)-approved packaging but for which a doctor might still prescribe the drug.

Some off-label uses for Xanax include the following:

Some off-label uses for clonazepam include the following:

Although clonazepam and Xanax are similar types of drug, there are times when one might be better to use than the other.

Xanax is not a seizure medication. Therefore, a person trying to control and treat seizures may find clonazepam more useful.

People with anxiety disorders should make an appointment with their doctor to discuss the various treatment options and the pros and cons of each.

The doctor will ask about the person’s symptoms and medical history. They will consider any current medication the individual is taking before advising which prescription is most suitable.

Some people’s bodies react badly to particular medications, or the drug may be ineffective. If this is the case, a person should talk to their doctor, who can make an alternative recommendation.