Mirtazapine Side Effects. Dementia In Elderly

Last Updated: December 19, 2019

Authored by Sharon Levy, MD, MPH

Similar to other medications, Remeron side effects may occur at the initial stages of taking the drug or over time. These side effects of Remeron may be mild in some patients and go away after a while. However, others may experience more severe side effects. Therefore, patients taking Remeron should seek medical assistance to help them manage these side effects.

What Are The Side Effects Of Mirtazapine?

Side effects of Remeron may vary from one patient to another depending on age and duration of use among several other factors. It is advisable not to drive or operate heavy machinery, especially during the initial stages of use. Mirtazapine can cause drowsiness affecting the patient’s ability to think and act quickly.

Furthermore, patients are also advised not to mix mirtazapine and alcohol as this may increase the nervous system side effects of mirtazapine such as drowsiness and dizziness.

Common Remeron Adverse Reactions

These Remeron common side effects are experienced by a majority of patients and may include:

  • sleepiness
  • increased appetite
  • weight gain
  • dry mouth
  • constipation
  • dizziness
  • strange dreams
  • generalized weakness
  • high cholesterol
  • increased hunger

remeron side effects: common and rare

Rare Mirtazapine Side Effects

These are also far less common mirtazapine adverse effects:

  • agitation
  • hallucinations
  • fever
  • uneven heartbeat
  • loss of coordination and feeling unsteady
  • stiff muscles
  • white patches or sores inside mouth or lips
  • nausea
  • trouble concentrating
  • chills
  • confusion
  • overactive reflexes
  • flu-like symptoms
  • suicide ideation
  • excessive happiness or irritability
  • angle closure glaucoma

Postmarketing Mirtazapine Side Effects

The following are some of the postmarketing adverse reactions:

  • impaired concentration
  • cerebrovascular disorder
  • hypercholesterolemia
  • psychomotor restlessness
  • increased creatine kinase blood vessels
  • toxic epidermal necrolysis

Remeron Side Effects In Elderly

Adverse mirtazapine side effects in elderly patients may be directly linked to decreased renal functions, a slower metabolism, and excretion of medication. Since elderly patients are more vulnerable to any medications, care should be taken when prescribing a correct Remeron dosage.

What Side Effects Does Remeron Causes In The Elderly?

In fact, there aren’t any specific mirtazapine side effects among geriatric patients as a result of their age. The point is that the common and rare Remeron side effects can happen with a higher likelihood.

However, elderly patients are more likely to have unusual drowsiness related directly to mirtazapine side effects. Age-related kidney problems are also more frequent in elderly patients.

remeron and dementia in elderly

Does Remeron Cause Dementia?

Research by the U.S. National Library of Medicine proposes that some antidepressant medications are associated with an increased risk of dementia. Similarly, a Nationwide Cohort Study in Taiwan found that 3.08% of a 29,095 sample study population prescribed to the drug had experienced dementia as one of the mirtazapine’s adverse effects. That is why Remeron is associated with the development of dementia, especially in elderly patients.

Remeron Sexual Side Effects

Furthermore, some antidepressant drugs used to treat this condition also hinder sexual functions. Mirtazapine, on the other hand, has a lower tendency to sexual dysfunction as compared to other antidepressant medications. Nonetheless, it has been linked to decreased libido, delayed orgasm, and erectile dysfunction. Despite this, treatment for major depressive disorder is one of the mirtazapine uses because compared to other antidepressants, it exhibits lower cases of sexual dysfunction.

Can Mirtazapine Cause Serotonin Syndrome?

When patients take two or more antidepressant drugs from two pharmacologic classes, drug interactions may occur, leading to severe serotonin toxicity. Serotonin syndrome is not a direct side effect of mirtazapine but can be induced in combination with other serotonergic agents such as methadone and sertraline. Mirtazapine drug class is a tetracyclic antidepressant. It works by blocking the reabsorption of serotonin in the brain. Therefore, overdosing on Remeron may cause an increase in serotonin levels in the brain, too.

Can Remeron Cause Tinnitus?

No, Remeron does not cause tinnitus. Even though tinnitus is not one of the side effects of Remeron, other classes of antidepressants like selective serotonin reuptake inhibitors and tricyclic antidepressants have been thought to worsen the condition.  If a patient experiences tinnitus while on selective-serotonin reuptake inhibitors such as Celexa and Lexapro, they should consult a doctor who may prescribe an alternative class of antidepressants.

restless legs as remeron side effect

Can Remeron Cause Restless Leg Syndrome?

The joint use of Remeron with tramadol or other dopamine-blocking agents can increase the risk of restless leg syndrome as a side effect of Remeron medication. Doctors are, therefore, advised to watch carefully for the development of RLS when the drug is administered to patients who are taking any dopamine-blocking agents.

Can Mirtazapine Cause Anxiety?

Yes, however, very rarely. There are about 1% of the patients who experience anxiety as a mirtazapine side effect. The Remeron effect is usually common during the first few weeks of treatment. Patients are advised to check with a doctor if they experience changes in their mental well being.

Do The Side Effects Of Mirtazapine Go Away?

Yes, most of the common Remeron side effects go away after the first weeks of being on the medication. Many people also take mirtazapine without any adverse reactions or with only a few mild adverse reactions.

Mirtazapine Risks: How To Manage Them

Some of the usual Remeron side effects are sleepiness, weight gain, dry mouth, constipation improve with time once the body adjusts to the medicine. If a patient is experiencing fatigue or drowsiness as a mirtazapine side effect, they should seek medical assistance from a doctor and suggest taking medicine at a different time of day. An increase in appetite may cause undesirable weight gain. Mirtazapine weight gain can be managed through early intervention and proper dietary regimens. Patients are also advised to drink plenty of water, eat high-fiber foods, and exercise regularly if constipation occurs.

If the patients are unable to manage the health hazards at home, they can refer to rehab for drug addicts. These facilities can also help in case of medication abuse or misuse. The addiction treatment programs here are designed in a way to meet all the specific needs of patients, as well as ensure a long-standing recovery.

Page Sources

  1. Magnuson T & Keller BK. TREATMENT FOR GERIATRIC DEPRESSION. The Nebraska Geriatrics Education Center. 2009. https://www.unmc.edu/media/intmed/geriatrics/nebgec/pdf/ltcseries/genericstreatmentforgeriatricdepression.pdf.
  2. Then CK, Chi NF, Chung KH, et al. Risk analysis of use of different classes of antidepressants on subsequent dementia: A nationwide cohort study in Taiwan. PLoS One. 2017; 12(4): e0175187. doi:10.1371/journal.pone.0175187. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5383251/.
  3. ANTIDEPRESSANTMEDICATION &RISK OF DEMENTIA. A Nationwide Cohort Study in Taiwan. Graduate Institute of Medical Sciences. 2017. https://www.alz.co.uk/sites/default/files/conf2017/o06-06-chee-kin-then-antidepressant-medication-and-risk-of-dementia.pdf.
  4. Dealing with sexual side effects of antidepressants. Harward Health Publiishing. 2019. https://www.health.harvard.edu/mind-and-mood/dealing_with_sexual_side_effects.
  5. Lahon K, Shetty HM, Paramel A, Sharma G. Sexual dysfunction with the use of antidepressants in a tertiary care mental health setting - a retrospective case series. Journal of Pharmacology & Pharmacotherapeutics. 2011; 2(2): 128–131. doi:10.4103/0976-500X.81913. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3127346/.

Published on: November 25th, 2019

Updated on: December 19th, 2019

About Author

Sharon Levy, MD, MPH

After successful graduation from Boston University, MA, Sharon gained a Master’s degree in Public Health. Since then, Sharon devoted herself entirely to the medical niche. Sharon Levy is also a certified addiction recovery coach.


Leave a comment