IRC-Galleria

Common side effects of mirtazapine include dizziness, blurred vision, sedation, drowsiness or somnolence, malaise or lassitude, increased appetite or hyperphagia and subsequent weight gain, agitation or restlessness, irritability or aggression, apathy or anhedonia or emotional blunting, excessive mellowness or calmness, dry mouth or xerostomia, difficulty swallowing or dysphagia, shallow breathing or hypoventilation or respiratory depression, constipation, decreased body temperature or hypothermia, pupil constriction or miosis, enhanced libido and sexual function or aphrodisia, wet dreams or nocturnal emission, spontaneous orgasm, loss of balance, vertigo, and restless legs syndrome (RLS). Mirtazapine has also occasionally been reported to cause mild psychedelic effects in some patients, including mental imagery, auditory and visual hallucinations, and particularly, vivid, bizarre, and even lucid dreams or nightmares. Most of these side effects are generally mild and become less prominent over time.

Rare and potentially serious adverse reactions may include allergic reaction, abnormal fluid accumulation or edema, fainting or syncope, seizures or convulsions, bone marrow suppression or myelotoxicity, ineffective myeloid blood cell production or myelodysplasia, and white blood cell reduction or agranulocytosis (occurs in 1/1,000 patients).

Mirtazapine seems to have lower risk of many of the side effects encountered with related antidepressants, such as decreased appetite or anorexia, insomnia, nausea and vomiting or emesis, diarrhea, urinary retention or ischuria, increased body temperature or hyperthermia, increased perspiration or sweating, pupil dilation or mydriasis, or sexual dysfunction (consisting of loss of libido and anorgasmia).

In general, antidepressants may have the capacity to exacerbate some patients' depression or anxiety or cause suicidal ideation, particularly when first starting treatment. As of 2001[update], there was no evidence that mirtazapine differs from other antidepressants in this regard, but studies of such rare effects need to follow a larger number of participants over a longer time to give a clearer picture either way.