Remeron Weight Gain And How Mirtazapine Causes It

Last Updated: February 7, 2020

Authored by Sharon Levy, MD, MPH

Remeron and weight gain is an object of many studies at the moment. Remeron can cause weight gain in either a short or long-time period, and there are several reasons for this. In addition to depression-related arguments, there are some individual ones that also contribute to mirtazapine weight gain.

Does Remeron Cause Weight Gain?

An atypical antidepressant Remeron can cause weight gain in patients who take this drug during depression treatment. In addition to depression, Remeron uses include anxiety, PTSS, appetite stimulation, and nausea treatments.

The Remeron weight gain is also connected with a number of health consequences. An increase in body mass is directly related to metabolic abnormalities. The majority of the consequences includes worsening of the preexisting comorbidities that are connected to obesity such as:

  • insulin resistance and type 2 diabetes mellitus
  • hypertension
  • dyslipidemia
  • cardiovascular disease
  • stroke
  • sleep apnea
  • gallbladder disease
  • hyperuricemia and gout
  • osteoarthritis

Why Does Mirtazapine Cause Weight Gain?

Mirtazapine does affect a patient’s body size, and there are certain reasons behind this. While the exact correlation between Remeron and weight gain is not entirely studied, scientists consider the issue to be multifactorial in nature. At the moment, there are several hypotheses concerned with the biochemical dependencies that can explain Remeron-induced body mass increment. Note, that extra pounds can be a side effect of the drug’s impact on histaminergic and 5-HT2C receptors.

Increased Appetite And Metabolism Decrease

This hypothesis is based on the connection between an increase in body mass due to Remeron and the malfunction of neurobiological controls that normalize food consumption. Generally, a study shows a basal metabolic rate decrease in those who are taking antidepressants.

remeron causes weight gain

Food Cravings (Carbohydrates)

It is critical that patients who take Remeron monitor their caloric intake. A patient who suffers from depression and undergo Remeron treatment often report an increase in food cravings. They are likely to eat more carbohydrates and sweet foods. At the same time, however, no studies prove that such behavior prevents a subsequent body mass increment if a patient is taking the drug. Thus, Remeron and weight gain resulting from food craving is still an issue that requires further investigations.

Fat Mass Increase And Hormone Levels

Some antidepressants, including Remeron, can contribute to extra pounds due to fat mass increase. At the same time, fat mass gain and serum leptin levels are related variables. Treatment with amitriptyline or mirtazapine is associated with an increase in leptin secretion beyond the change in weight. A fat cell leptin ensures that the hypothalamus receives negative feedback signaling food satiation. Thus, the hypothesis states that Remeron-induced body mass increase is conditioned upon the changed leptin levels.

Drug Interaction Effects

Gaining extra pounds is one of the side effects of mirtazapine, and it can be more likely to occur in the case of drug interactions. Taking Remeron, a patient should know which drugs can be used sideline and learn as much as possible about mirtazapine and weight gain connection.

weight gain effect of remeron

Additional Factors Affecting The Severity Of Weight Gain

Some of the other factors that contribute to putting on some pounds include dosage, a period of taking the drug, and also individual characteristics.


Different dosages of the antidepressant have different impacts on a person. The Remeron dose depends upon a patient’s size before the treatment session. The mirtazapine weight gain dosage does not exceed the prescribed one. However, with a higher than the average one, a patient is more likely to put on somebody mass and visa versa. A patient can experience mirtazapine benefits if only the dosage is correct.

What is more, higher mirtazapine doses are affecting one’s physiological functions, as well as neurochemistry. In cases when such changes are considerable, Remeron will also alter a patient’s fat regulation, glucose levels, and leptin levels.

Period Of Taking The Drug

The period of taking medication can considerably contribute to the problem. Just as in the case with any remedy, a long-termed treatment leads to drug tolerance. The problem with this is that a patient does not feel the effect and wants to get more to receive the desired alleviation.

When the dose is considerably higher, a person undermines the homeostatic functioning of the organism and alters its neurochemistry. Such behavior ends up putting on even more kilos. However, Remeron does all these neurochemistry alterations starting from the first weeks.

Individual Characteristics

One should not ignore the role of such individual characteristics as genetics, age, gender, etc. Even though antidepressants are often associated with the risks of overweight, depression itself stimulates metabolic disorders and excess in body mass. There are several behaviors characteristic of depressed people that contribute a lot to gaining extra pounds.

how fast remeron causes weight gain

How Much And During What Time One Can Gain Extra Weight?

Remeron can trigger weight gain within a short and long period. Depending on many factors, including individual ones, an increase in body mass may vary from a few pounds to about 30 lbs.

A study published in the Journal of Clinical Psychiatry reports that over 6 weeks the participants gained roughly 8 lbs. Hopefully, this gained fat mass is generally easy to lose after discontinuation of Remeron.

How To Avoid Or Manage Remeron Weight Gain

A patient should consult a doctor regarding any question to prevent or manage Remeron weight gain. Before starting treatment with mirtazapine, one should find out the potential risks, undergo testing, and inform a doctor about any illnesses and drugs a patient already takes. Also, experiencing Remeron weight gain, users should avoid self-treatment.

What is more, it is possible to manage or prevent Remeron fat mass increment if consultations with a doctor are regular. Early intervention will release a patient from unpleasant outcomes. Importantly, one should continue making blood tests to check the levels of sugar, serum lipids; also, it is crucial to monitor abdominal circumference, as well as blood pressure. Remember that much depends on a patient’s conscience in terms of Remeron weight gain.

Timely Medical Help Is The Shortest Way To Recovery

Remeron and weight gain is an issue that is not entirely studied yet; however, this drug can cause weight increment under certain circumstances. Prevention of weight increase is possible due to regular consultations with a doctor and the responsible attitude of a patient. Nevertheless, if a patient already has a problem with weight due to Remeron misuse/abuse, they must get professional help from addiction centers as soon as possible. Substance abuse treatment and therapies in these facilities offer a wide range of services to help to recover.

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Published on: November 25th, 2019

Updated on: February 7th, 2020

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.


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