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Antidepressant (atypical / noradrenergic and specific serotonergic)

Mirtazapine: uses, side effects & precautions

Also known as Remeron, Zispin.

Ces informations sont fournies à titre indicatif uniquement et ne constituent pas un avis médical. Consultez toujours un professionnel de santé qualifié pour toute préoccupation médicale personnelle. En cas d'urgence, appelez votre numéro d'urgence local.

What it is used for

  • Depression
  • Depression with poor sleep or appetite (sometimes chosen for these effects)
  • Anxiety associated with depression

How it works

Mirtazapine works on serotonin and noradrenaline systems in the brain through a different mechanism from most other antidepressants. It is thought to improve mood and often promotes sleep and appetite.

How it is taken

Usually available as standard tablets and as orodispersible tablets that dissolve in the mouth. It is taken by mouth, commonly at bedtime because it can cause drowsiness. Take it exactly as your doctor or pharmacist directs and follow the label; do not stop suddenly.

No doses here on purpose. The right strength and schedule depend on you — only a doctor or pharmacist should set them. Always follow your prescription and the label.

Common side effects

  • Drowsiness or sedation
  • Increased appetite and weight gain
  • Dry mouth
  • Constipation
  • Dizziness
  • Vivid dreams
  • Headache
  • Swelling of ankles or feet

Serious effects — get help

  • New or worsening suicidal thoughts, especially early on (seek urgent help)
  • Signs of infection such as sore throat, fever or mouth ulcers (rare effect on blood cells - seek prompt advice)
  • Serotonin syndrome: agitation, fever, muscle twitching, confusion
  • Yellowing of skin or eyes (liver problem)
  • Seizures
  • Severe allergic or skin reactions
  • Switch into mania in people prone to it

If a reaction is severe — for example trouble breathing, swelling of the face or throat, or collapse — go to the nearest emergency room now or call your local emergency number. Do not wait for an online consultation.

Interactions to watch

  • MAOI antidepressants (must not be combined)
  • Other sedating medicines, sleeping tablets, strong painkillers and alcohol
  • Other serotonin-raising medicines
  • Some medicines processed by the liver
  • Medicines affecting heart rhythm

Who should take care

  • Report any signs of infection promptly because of a rare effect on white blood cells
  • Tell your clinician if you are pregnant, planning pregnancy or breastfeeding
  • Use with caution with liver or kidney problems, epilepsy, heart conditions or diabetes
  • May cause significant weight gain and daytime drowsiness
  • Do not stop suddenly; taper under medical guidance

Frequently asked questions

Why is mirtazapine often taken at night?
It tends to be sedating, especially at lower amounts, so taking it at bedtime can help with sleep and reduce daytime drowsiness. Follow the timing your clinician advises.
Will it make me gain weight?
Mirtazapine commonly increases appetite and can lead to weight gain. Tell your clinician if this is a concern, as there may be alternatives.
How quickly does it help sleep and mood?
Improved sleep and appetite can appear early, while the full effect on mood usually takes 4-6 weeks. Keep taking it as prescribed.
I have a sore throat and fever - does it matter?
Rarely, mirtazapine can affect white blood cells that fight infection. If you develop a sore throat, fever or mouth ulcers, contact a clinician promptly so they can check.
Is Mirtazapine safe to take?
For most people it is safe when taken exactly as a doctor or pharmacist advises and as printed on the label. Tell your clinician about your other medicines and health conditions, and seek urgent care for any serious reaction.

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