Mirtazapine and Clonazepam: Is there any possible interaction?

In this blog post, we are going to talk about the possible interactions between mirtazapine and clonazepam. Both of these meds are prescription medications and are associated with a number of side effects. 

This blog will cover the safety and efficacy of the concomitant use of mirtazapine and clonazepam. 

Is there any possible interaction between mirtazapine and clonazepam?

The concomitant use of mirtazapine (Remeron) and clonazepam (Klonopin) may increase the risk of drowsiness, low mental alertness, impaired motor functions, confusion, forgetfulness etc, but these side effects depend on the doses you’re at. 

These side effects can vary from person to person and they depend on the doses of this combination. If you are at low doses, the most common thing you can experience is dizziness and sleepiness. 

However, higher doses can break a havoc on a person’s mind and it can cause major complications. Elderly patients are more susceptible to these side effects and may suffer from additional effects like memory loss, impairment of motor coordination and troubled judgement. 

However, these two meds are still used together. Doctors usually adjust the doses when they prescribe more than one medication. Pre-existing health conditions are also considered before determining the appropriate dose. 

Medications are not solely responsible to produce effects as your body’s response to them can make a huge difference. Some people are extremely sensitive and they can’t even bear one medication, let alone the combination of more meds. 

This can result in therapeutic failure and you have to discontinue the treatment. It is extremely important to inform your healthcare provider of all the medications you’re taking. Drug interactions should be an important consideration before taking two or more medicines together. 

Yes, drugs in combination are often used to achieve better therapeutic response but this is not the case with every interaction. 

Some drugs are highly incompatible with one another. They often cancel out each other’s effects or antagonise them. Some drugs are so incompatible that they end up changing the entire chemical composition of one another. 

Some interfere with metabolism or bioavailability (the rate and extent at which the active drug moiety enters systemic circulation/blood). This can lead to drug accumulation in different parts of the body. 

It is always advised to inform your healthcare provider of any medicine you take before getting a new prescription. Your doctor will make sure not to prescribe any such drug which might interfere with those you are already taking. 

How do mirtazapine and clonazepam differ from each other?

Mirtazapine (Brand name: Remeron) is an antidepressant. It does not belong to any typical class of antidepressants and its mechanism of action is different from SSRIs and SNRIs. It does not block the reuptake of serotonin by any pathway. 

Mirtazapine belongs to the tetracyclic antidepressants. It has a dual mode of action. Mirtazapine is believed to be responsible for the activation of 5-HT1 receptors, which are one of the serotonin receptors. This antidepressant also acts on the noradrenergic system. 

Experts believe that mirtazapine enhances the stimulatory action of the noradrenergic system which increases the secretion of serotonin. It also prevents the inhibitory action of the noradrenergic system which hinders the release of serotonin. 

This way, it actively increases the amount of this excitatory neurotransmitter in your system. Mirtazapine can be used to treat the following health conditions:

  • Depression 
  • Anxiety 
  • Treatment resistant depression 
  • Depression in elderly patients
  • Post-operative nausea
  • Alcohol dependence
  • Insomnia or inability to fall asleep 
  • Neuropathic pain
  • Inability to feel hungry/hunger suppression

Clonazepam, on the other hand, is a brand name for diazepam, which is one of the oldest benzodiazepines. It is used to help control anxiety, convulsions and panic attacks. This medication basically mimics inhibitory chemicals in your brain, like GABA, to control the excessive neuronal activity. 

Antidepressants, including mirtazapine, do not work overnight and they are expected to kick in within 4-6 weeks of your treatment. However, these meds start to produce the side effects way earlier. 

One of the most commonly experienced early side effects of mirtazapine is anxiety. This anxiety can be controlled by clonazepam or any other benzodiazepine. 

The treatment is usually continued till your antidepressant kicks in. These meds together can control multiple overlapping symptoms of anxiety and depression. 

These symptoms include:

  • Restlessness 
  • Extreme distress
  • Irritability 
  • Suicidal behavior 
  • Inability to engage in daily life activities 
  • Weight loss or gain, depending on the effect of the condition on eating habits
  • Excessive sweating 
  • An urge to get isolated
  • Hopelessness 
  • Worthlessness 
  • Confusion 
  • Social disconnection 

A few studies indicate that benzodiazepines may play an important role in the management of depression and can be used in combination with antidepressants for the treatment of major depressive disorder (MDD). 

The same study revealed that GABA can make an impact on your depression through GABA depression theory and benzodiazepines can control this effect. 

Make sure you ask your healthcare provider before using any medication. It is not recommended to self medicate, as it may make your symptoms much worse. 

What are the safety concerns with the use of mirtazapine and clonazepam?

Both mirtazapine and clonazepam are associated with few side effects, which can vary from person to person. Side effects are not just the effects of your drug but also how your body responds to the drug. 

Usually clonazepam is well tolerated, but some people may suffer from the side effects and might even stop the treatment because of them. It depends on the pre-existing health conditions as well. One of the side effects of benzodiazepines include respiratory depression, which is dose dependent. 

A person with normal respiratory function might not even notice this side effect on the normal therapeutic dose, but people with chronic breathing disorders like asthma, chronic obstructive pulmonary disease (COPD) and emphysema etc, can suffer from significant breathing difficulties. 

Similarly, mirtazapine is considered safe to be used in cardiac patients, but it could cause QT elongation and make pre-existing arrhythmia even worse. Clonazepam is also known for causing an addiction, which is why it is not suitable for prolonged use. 

Doctors usually recommend using it as long as your antidepressant kicks in. After that, both anxiety and depression can be managed by mirtazapine and clonazepam is slowly tapered off. You see, it’s not always about the drug, but also your body’s reaction to it. 

Both pharmacodynamics (how a drug affects your body) and pharmacokinetics (how your body affects a drug) are considered. 

It is always best to consult your healthcare provider and be certain that the combination of meds you’re about to use is compatible with any underlying health condition you might have. It is also important to make sure that all of your meds are compatible with one another. 

The doses at which you’re taking clonazepam and mirtazapine play the most important role in the safety and efficacy profile of the concomitant use of these meds. High doses of both the meds can make you vulnerable to CNS side effects. 

Clonazepam is very potent and low doses are sufficient to provide therapeutic response. In usual practice, 0.5 mg clonazepam should be enough to control your anxiety, till your mirtazapine kicks in, which is also started with a lowest effective dose. 

Usually 10 mg is prescribed. Make sure you don’t take more than your healthcare professional has recommended. Higher doses will lead to much more pronounced drowsiness, dizziness and mental confusion. 

The timing at which you take your medications also makes a huge difference. Usually, it is recommended to take your mirtazapine in the morning (if it does not cause tiredness or sleepiness) and your clonazepam at bedtime, as it induces sleep and slows down your brain.

If these timings do not suit you or you take both of these at bedtime and still feel lethargic and tired during the day, talk to your doctor. 

Your doctor may weigh the pros and cons of this concomitant treatment in accordance with your side effects and will determine if it’s worth continuing it. 


In this blog post, we have discussed the concomitant use of mirtazapine and clonazepam. These may interact with each other and increase the risk of sedation, dizziness, fatigue, impaired senses and difficulty in concentrating. 

Elderly patients are more susceptible to these side effects and may suffer from additional effects like memory loss, impairment of motor coordination and troubled judgement. However, these two meds are still used together. 

The dose at which you take these two drugs can make a huge impact on your health. Make sure you use these two meds only when the combination treatment is preferred by your mental healthcare professional. Do not start any other medication along with your prescribed antidepressant. 

FAQs: mirtazapine and clonazepam

Can clonazepam and mirtazapine be taken together?

Yes , clonazepam and mirtazapine can be taken together if prescribed by your healthcare provider. The concomitant use may increase the risk of drowsiness, low mental alertness, impaired motor functions, confusion, forgetfulness etc, but these side effects depend on the doses you’re at. 

These side effects can vary from person to person and they depend on the doses of this combination. If you are at low doses, the most common thing you can experience is dizziness and sleepiness. 

What medications should not be taken with mirtazapine?

  • Monoaminoxidase inhibitors (MAOIs). The combination use can increase the risk of serotonin syndrome. 
  • Non-steroidal anti-inflammatory drugs (NSAIDS). The combination use can increase the risk of bleeding. 
  • Pimozide. The concomitant use can increase the plasma concentration(availability of a drug in the blood) of pimozide to much higher levels. It can result in life-threatening arrhythmia.
  • Controlled substances, including all narcotic analgesics. The concomitant use can cause severe psychological side effects. 
  • Mood stabilisers 
  • Alcohol 

Can you take clonazepam with antidepressants?

Yes, you can take clonazepam together with antidepressants. This combination is often prescribed by healthcare professionals to calm your anxiety down, while your antidepressant takes its time to start working in your system. This combination can also be used for the treatment of depression comorbid with anxiety and insomnia. 

Is 30mg of mirtazapine good for anxiety?

Yes, 30mg mirtazapine is good for anxiety. Anxiety is a mental health condition associated with general worry or anxiety about pretty much everything without having any logical reason. People suffering from GAD worry about small matters related to family, friends, relationships, study, work, health, wealth etc. 

What drugs should not be taken with clonazepam?

  • Antifungals and antivirals. They may inhibit the metabolism of clonazepam and cause toxicity. 
  • Antiepileptics. The concomitant use may decrease the beneficial effects of clonazepam. 
  • Anti-allergy medications. The concomitant use increases the risk of sedation 
  • Narcotic analgesics or any other controlled substance. The concomitant use can cause serious CNS side effects. 
  • Sleeping pills
  • Other anxiolytics and tricyclic antidepressants (TCAs). 


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