Mirtazapine for Sleep: Uses, Side Effects & Alternative Insomnia Treatments

Dr. Colleen Ehrnstrom's profile picture
Dr. Colleen Ehrnstrom, PhD
Oct 31, 20216 min read
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Good sleep can be hard to come by. Studies show that more than nine million adults in the U.S. use prescription sleep aids.1 Additionally, one out of three older adults turns to prescription drugs for better rest.2

Some prescription sleep medications, including mirtazapine, are antidepressants. These medications can change brain chemistry to strengthen processes that lead to sleep. Some people find that these drugs can act as a quick fix for insomnia, while others have had better luck with other treatments.

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What Is Mirtazapine?

Mirtazapine, which also goes by the brand name Remeron, is a type of tetracyclic antidepressant. It is approved by the U.S. Food and Drug Administration (FDA) to treat major depressive disorder.3 Doctors may also choose to prescribe mirtazapine “off-label” to help with various types of anxiety disorders, obsessive-compulsive disorder, and insomnia.4

Mirtazapine increases levels of chemical messengers called neurotransmitters in the brain. In particular, it boosts the effects of serotonin and noradrenaline. These neurotransmitters help control mood, stress levels, and sleep/wake cycles.5

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Does Mirtazapine Help With Sleep?

Sleepiness is one of the most common side effects of mirtazapine.3 People who take this drug may soon start to feel tired.

Research has found that mirtazapine may help treat insomnia. In a 2018 study, researchers gave mirtazapine to 28 men with depression, suicidal thoughts, and insomnia. Six people dropped out of the study due to side effects, but the remaining study participants saw their insomnia symptoms improve or disappear.6

Additionally, in a review of 15 studies of people with major depressive disorder, researchers determined that mirtazapine could improve insomnia symptoms. Those who took the drug had higher-quality sleep and spent more time asleep while at night.7

How Does Mirtazapine Work?

To understand how mirtazapine can help, it is useful to grasp the impact of depression on sleep. Sleep is broadly divided into two phases: rapid eye movement (REM) sleep and non-rapid eye movement (NREM) sleep. You need to spend a certain amount of time in both phases to feel fully rested.8

Depression can impact these sleep phases. Studies show that people with depression reach REM stage more quickly and spend more time in this sleep stage throughout the night. They also spend less time in slow-wave sleep — the deepest sleep stage, during which the body spends the most time healing and rebuilding tissues. In this way, depression has a negative effect on overall sleep quality.9

People who take mirtazapine take longer to reach REM sleep. They also spend more time in deeper sleep stages. The end result is that they tend to get higher-quality, more rejuvenating rest.10

Unfortunately, the effects of mirtazapine are often short-lived. Much like other sleeping medications, the body quickly adapts to this drug. Although mirtazapine works well to induce sleep temporarily, it is often much less effective over the long term.10

Mirtazapine Recommended Dosage

Doctors most often recommend taking 15 mg of mirtazapine to start with. If this dosage isn’t helping treat your symptoms, your doctor may recommend slowly and gradually increasing your dose.4

Some people may need lower mirtazapine doses. The drug may have stronger effects in elderly adults or in people with kidney or liver problems, so these groups of people may be given a smaller starting dose.4 Always follow your doctor’s instructions when it comes to starting or changing a drug regimen.

Mirtazapine Side Effects

Mirtazapine use is associated with several side effects. Some of the most common include:12

  • Tiredness
  • Dizziness
  • Dry mouth
  • Nausea or vomiting
  • Constipation
  • Feelings of anxiety or confusion
  • Increased appetite and weight gain

Certain serious side effects are a cause for concern. Tell your doctor right away if, while taking mirtazapine, you develop chest pain, a rapid heartbeat, seizures, or flu-like symptoms such as a fever or sore throat.

This drug should not be taken along with certain medications, including other antidepressants or sleeping pills. Make sure to tell your doctor about all drugs, vitamins, and supplements you are taking before you start using mirtazapine.12

In addition, mirtazapine can cause several sleep-specific side effects.

Sleep Disorders

Although mirtazapine may help treat insomnia, it can also lead to other types of sleep disorders. Restless leg syndrome (RLS), a condition that creates uncontrollable urges to move the legs, occurs in up to three out of ten people taking mirtazapine.13 Additionally, this drug can cause periodic limb movements of sleep (PLMS), a disorder that causes repetitive or jerking movements while asleep, in up to two-thirds of people who take it.14

It is also important to know that if you are relying on mirtazapine to help you sleep, you may experience insomnia once you stop using the drug or change your dose.15 This is why it is important to consult your doctor before beginning, modifying, or discontinuing a medication.

Daytime Drowsiness

Due to mirtazapine’s sedating properties, approximately 54% of users experience daytime drowsiness.4 This is particularly worrying for people suffering from depression, which itself causes sleepiness and exhaustion. Taking mirtazapine may make this situation worse.

Strange Dreams

Stopping mirtazapine suddenly can cause strange, vivid dreams, and nightmares. However, this phenomenon is rare.16

Alternatives to Mirtazapine for Insomnia

People who have trouble sleeping frequently turn to medications first. Unfortunately, they are unaware of safer, more effective therapies.

For example, changing your sleeping habits can help you sleep better over time. Sleep habits create a reliable and predictable pattern that your mind and body can more easily follow.17

You can prepare for a restful night of quality sleep by relaxing before bed. A warm bath or a relaxing massage are excellent options. It’s also a good idea to make your surroundings conducive to better sleep. Set your thermostat to a cooler temperature, thoroughly cover your windows, and remove all unnecessary distractions. You can even experiment with different sleeping positions to see what works best.

Furthermore, what you do during the day has a significant impact on how well you sleep. Longer naps can disrupt your sleep drive — the feeling of needing to sleep that increases throughout the day — so you may want to consider taking shorter naps. Exercising during the day may also help you relax and sleep better in the evenings.17

If you still have trouble sleeping, your doctor may prescribe cognitive behavioral therapy for insomnia (CBT-I).

Why CBT-I May Be the Best Cure for Insomnia

CBT-I is an evidence-based and clinically-proven approach for treating sleep disorders. It is considered the “gold standard” of insomnia treatment and is recommended by expert groups including the American College of Physicians and the American Academy of Sleep Medicine.18

CBT-I provides a comprehensive plan that strengthens your sleep drive and teaches you to calm your mind. It is highly effective, with research showing it helps up to four out of five people achieve healthy and restorative sleep.19 Furthermore, unlike sleeping pills and antidepressants that are only helpful for as long as you take them, the beneficial effects of CBT-I are ongoing.

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  1. Chong, Y., Fryar, C.D., & Gu, Q. (2013, August). Prescription Sleep Aid Use Among Adults: United States, 2005-2010. Centers for Disease Control and Prevention. https://www.cdc.gov/nchs/products/databriefs/db127.htm

  2. Malani, P. (2017, September 27). 1 in 3 Older Adults Take Something to Help Them Sleep — But Many Aren’t Talking to Their Doctors. University of Michigan Institute for Healthcare Policy & Innovation. https://ihpi.umich.edu/news/1-3-older-adults-take-something-help-them-sleep-%E2%80%93-many-aren%E2%80%99t-talking-their-doctors

  3. U.S. Food and Drug Administration. (2020, March). Remeron (mirtazapine) Tablets, for Oral Use: Highlights of Prescribing Information. https://www.accessdata.fda.gov/drugsatfda_docs/label/2020/020415s029,%20021208s019lbl.pdf

  4. Patel, A. K., Reddy, V., & Araujo, J. F. (2021). Physiology, Sleep Stages. In StatPearls. StatPearls Publishing. https://www.ncbi.nlm.nih.gov/books/NBK526132/

  5. Anttila, S. A., & Leinonen, E. V. (2001). A review of the pharmacological and clinical profile of mirtazapine. CNS drug reviews, 7(3), 249–264. https://doi.org/10.1111/j.1527-3458.2001.tb00198.x

  6. Gandotra, K., Chen, P., Jaskiw, G. E., Konicki, P. E., & Strohl, K. P. (2018). Effective Treatment of Insomnia With Mirtazapine Attenuates Concomitant Suicidal Ideation. Journal of clinical sleep medicine : JCSM : official publication of the American Academy of Sleep Medicine, 14(5), 901–902. https://doi.org/10.5664/jcsm.7142

  7. Dolder, C. R., Nelson, M. H., & Iler, C. A. (2012). The effects of mirtazapine on sleep in patients with major depressive disorder. Annals of clinical psychiatry : official journal of the American Academy of Clinical Psychiatrists, 24(3), 215–224.

  8. Institute of Medicine (US) Committee on Sleep Medicine and Research. (2006). Sleep Physiology. In H.R. Coten & B.M. Altevogt (Eds), Sleep Disorders and Sleep Deprivation: An Unmet Public Health Problem. https://www.ncbi.nlm.nih.gov/books/NBK19956/

  9. Palagini, L., Baglioni, C., Ciapparelli, A., Gemignani, A., & Riemann, D. (2013). REM sleep dysregulation in depression: state of the art. Sleep medicine reviews, 17(5), 377–390. https://doi.org/10.1016/j.smrv.2012.11.001

  10. Leonard, S.D. & Karlamangla, A. (2015). Dose-Dependent Sedating and Stimulating Effects of Mirtazapine. Proceedings of UCLA Healthcare, 19. Available from https://proceedings.med.ucla.edu/wp-content/uploads/2016/11/Dose-Dependent-Sedating-and-Stimulating-Effects-of-Mirtazapine.pdf

  11. Jilani, T.N., Gibbons, J.R., Faizy, R.M., & Saadabadi, A. (2022, May 2). Mirtazapine. In StatPearls. StatPearls Publishing. https://www.ncbi.nlm.nih.gov/books/NBK519059/

  12. MedlinePlus. (2022, January 15). Mirtazapine. https://medlineplus.gov/druginfo/meds/a697009.html

  13. Rottach, K. G., Schaner, B. M., Kirch, M. H., Zivotofsky, A. Z., Teufel, L. M., Gallwitz, T., & Messer, T. (2008). Restless legs syndrome as side effect of second generation antidepressants. Journal of psychiatric research, 43(1), 70–75. https://doi.org/10.1016/j.jpsychires.2008.02.006

  14. Fulda, S., Kloiber, S., Dose, T., Lucae, S., Holsboer, F., Schaaf, L., & Hennings, J. (2013). Mirtazapine provokes periodic leg movements during sleep in young healthy men. Sleep, 36(5), 661–669. https://doi.org/10.5665/sleep.2622

  15. Berigan T. R. (2001). Mirtazapine-Associated Withdrawal Symptoms: A Case Report. Primary care companion to the Journal of clinical psychiatry, 3(3), 143. https://doi.org/10.4088/pcc.v03n0307a

  16. Mathews, M., Basil, B., Evcimen, H., Adetunji, B., & Joseph, S. (2006). Mirtazapine-induced nightmares. Primary care companion to the Journal of clinical psychiatry, 8(5), 311. https://doi.org/10.4088/pcc.v08n0510b

  17. Centers for Disease Control and Prevention. (2016, July 15). Tips for Better Sleep. https://www.cdc.gov/sleep/about_sleep/sleep_hygiene.html

  18. Feuerstein, S., Hodges, S. E., Keenaghan, B., Bessette, A., Forselius, E., & Morgan, P. T. (2017). Computerized Cognitive Behavioral Therapy for Insomnia in a Community Health Setting. Journal of clinical sleep medicine : JCSM : official publication of the American Academy of Sleep Medicine, 13(2), 267–274. https://doi.org/10.5664/jcsm.6460

  19. Bastien, C. H., Morin, C. M., Ouellet, M. C., Blais, F. C., & Bouchard, S. (2004). Cognitive-behavioral therapy for insomnia: comparison of individual therapy, group therapy, and telephone consultations. Journal of consulting and clinical psychology, 72(4), 653–659. https://doi.org/10.1037/0022-006X.72.4.653

Dr. Colleen Ehrnstrom's profile picture
Dr. Colleen Ehrnstrom, PhD

Dr. Colleen Ehrnstrom is a licensed clinical psychologist with a specialty practice in Acceptance and Commitment Therapy (ACT). Areas of expertise include insomnia and other sleep disorders, anxiety, and depression.

Dr. Ehrnstrom is not a medical provider and is not providing any recommendations regarding medications. Rather, she is sharing and reviewing the research as it relates to education when learning how best to treat insomnia.

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