Drug class · Nervous system

NaSSA antidepressants

Also known as: NaSSA, NaSSAs, NASSA, Noradrenergic and specific serotonergic antidepressants

The NHS groups antidepressants into types such as SSRIs, SNRIs, tricyclics and MAOIs, and lists mirtazapine as a noradrenaline and specific serotonergic antidepressant (NaSSA). Mirtazapine is the NaSSA covered on this site.

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Also called
NaSSA, NaSSAs, NASSA, Noradrenergic and specific serotonergic antidepressants

Mechanism of action

Pharmacology reviews describe mirtazapine as blocking alpha-2 receptors on nerve cells in the brain, which increases the release of noradrenaline and serotonin, and as also blocking 5-HT2 and 5-HT3 serotonin receptors. Unlike many other antidepressants, it is described as not inhibiting the reuptake of noradrenaline or serotonin. Blocking histamine H1 receptors is linked to its sedating effect.

Members of the class

mirtazapine

Members with a page on this site are linked.

Cautions

  • The NHS says mirtazapine is not usually recommended for anyone under 18.
  • The NHS says stopping an antidepressant suddenly can cause withdrawal symptoms, and the dose is usually reduced gradually.
  • The NHS says mirtazapine can be taken while breastfeeding if the baby is healthy.

Class warnings

  • The NHS side effects page says to call 999 or go to A&E now if a person has thoughts of harming themselves or ending their life, while the main NHS mirtazapine page says to call NHS 111. Samaritans can be reached free on 116 123 at any time. UK

Class interactions

WithEffectSource
St John's wortThe NHS says it should not be taken during mirtazapine treatment because it increases the risk of side effects. UK
WarfarinThe NHS says mirtazapine can affect warfarin, so the dose of warfarin may need to change. UK

Open the Drug Interaction Checker

Connected pages in detail

What each linked page on Anatomy Nexus covers, in a line, for NaSSA antidepressants.

Medications

  • Mirtazapine Mirtazapine is an antidepressant, prescribed mainly for depression and sometimes for obsessive compulsive disorder (OCD) and anxiety.
Educational content. A drug class page describes what a family of medicines has in common. Individual medicines differ in dose, licensing and interactions; treatment choices belong to a prescriber.