Remeron (mirtazapine) is a noradrenergic and specific serotonergic antidepressant (NaSSA) approved for the treatment of major depressive disorder (MDD). It works by enhancing noradrenergic and serotonergic neurotransmission through a unique mechanism distinct from SSRIs or SNRIs. Clinicians often prescribe it for its favorable side effect profile, including low incidence of sexual dysfunction and potential for improved sleep and appetite. Its efficacy and tolerability make it a valuable option in both initial and augmentation strategies for depression management.

Features

• Active ingredient: Mirtazapine
• Available in 15 mg, 30 mg, and 45 mg orally disintegrating tablets (ODT) and standard tablets
• Noradrenergic and specific serotonergic antidepressant (NaSSA) class
• FDA-approved for major depressive disorder (MDD)
• Rapid onset of action, with some effects noticeable within 1–2 weeks
• Minimal impact on serotonin reuptake pumps
• Metabolized primarily via CYP450 enzymes (CYP1A2, CYP2D6, CYP3A4)
• Half-life of approximately 20–40 hours

Benefits

• Effective relief from core depressive symptoms, including low mood, anhedonia, and psychomotor retardation
• May improve sleep architecture and reduce insomnia due to potent antihistaminergic effects at lower doses
• Can stimulate appetite and promote weight gain, beneficial in underweight or cachexic patients
• Lower risk of serotonin syndrome compared to SSRIs/SNRIs when used as monotherapy
• Generally well-tolerated with a lower incidence of nausea, vomiting, and sexual dysfunction than many antidepressants
• Useful in treatment-resistant depression as an augmenting agent or alternative

Common use

Remeron is primarily indicated for the treatment of major depressive disorder (MDD) in adults. It is also used off-label for generalized anxiety disorder (GAD), panic disorder, post-traumatic stress disorder (PTSD), and as an adjunct for insomnia or appetite stimulation in medically ill patients. Its sedating properties make it particularly useful for depressed patients with comorbid sleep disturbances. In geriatric populations, it is sometimes preferred due to its lower risk of causing hyponatremia or cardiac conduction abnormalities compared to some alternatives.

Dosage and direction

The recommended starting dose for Remeron is 15 mg once daily, preferably taken at bedtime due to its sedating effects. Dosage may be increased to 30–45 mg daily based on clinical response and tolerability. For patients with hepatic or renal impairment, a lower starting dose and careful titration are advised. Tablets should be swallowed whole with water; orally disintegrating tablets can be placed on the tongue without water. Dosage adjustments should be made at intervals of 1–2 weeks under medical supervision.

Precautions

Patients should be monitored for worsening depression, suicidality, or unusual changes in behavior, especially at initiation or dose changes. Use with caution in those with hepatic or renal impairment, epilepsy, cardiovascular disease, or a history of mania/hypomania. May impair alertness; advise against driving or operating machinery until response is known. Regular monitoring of weight, lipid profile, and blood glucose is recommended during long-term therapy. Abrupt discontinuation may lead to withdrawal symptoms; taper gradually.

Contraindications

Remeron is contraindicated in patients with known hypersensitivity to mirtazapine or any component of the formulation. Concomitant use with monoamine oxidase inhibitors (MAOIs) or within 14 days of discontinuing MAOI therapy is contraindicated due to risk of serotonin syndrome. Should not be used in patients with severe hepatic impairment. Not recommended during acute recovery phase after myocardial infarction.

Possible side effect

Common side effects include somnolence (54%), increased appetite (17%), weight gain (12%), dry mouth (25%), and dizziness (7%). Less frequently, patients may experience constipation, elevated triglycerides, abnormal dreams, or orthostatic hypotension. Rare but serious adverse effects include agranulocytosis, seizures, hyponatremia, and activation of mania/hypomania. Most side effects are dose-dependent and may diminish over time.

Drug interaction

Remeron may interact with CNS depressants (e.g., alcohol, benzodiazepines, opioids), increasing sedation. Strong CYP3A4 inhibitors (e.g., ketoconazole) can increase mirtazapine levels. Concomitant use with serotonergic drugs (e.g., SSRIs, tramadol) may elevate serotonin syndrome risk. May potentiate effects of antihypertensives. Use with caution with drugs that prolong QT interval. Avoid with MAOIs.

Missed dose

If a dose is missed, take it as soon as remembered unless it is close to the next scheduled dose. Do not double the dose to make up for a missed one. Consistent nightly administration is recommended to maintain steady-state concentrations and minimize sedation during waking hours.

Overdose

Symptoms of overdose may include disorientation, drowsiness, impaired memory, tachycardia, and hypertension. Severe overdose can lead to arrhythmias, convulsions, or coma. There is no specific antidote; treatment is supportive and symptomatic. ECG monitoring is advised. Gastric lavage or activated charcoal may be considered if presented early.

Storage

Store at room temperature (20–25°C or 68–77°F), away from light, moisture, and heat. Keep in the original container, tightly closed. Orally disintegrating tablets should be kept in the blister pack until use to protect from moisture. Keep out of reach of children and pets.

Disclaimer

This information is for educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment. Always seek the advice of your physician or other qualified health provider with any questions regarding a medical condition. Do not disregard professional medical advice or delay seeking it because of something you have read here.

Reviews

Clinical studies and post-marketing surveillance indicate that Remeron is effective in reducing depressive symptoms, with many patients reporting improved sleep and appetite within the first week. Some users note sedation as a challenging initial side effect, though it often diminishes with continued use. Long-term tolerability is generally favorable, though weight gain remains a concern for some individuals. Overall, it is regarded as a useful option, particularly in cases where SSRIs are ineffective or poorly tolerated.