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Selective Serotonin Reuptake Inhibitors (SSRI)

4.14 Antimuscarinic (anticholinergic) effects

Man rubbing his eyes Rare and very rare, but potentially serious adverse effects.

Antimuscarinic effects1, such as visual disturbance, tachycardia and urinary retention, can occur with SSRIs but they are generally less marked than with tricyclic antidepressants (and in some cases are negligible).

Risk-reduction measures

In patients with prostatic enlargement or angle-closure glaucoma an antidepressant with negligible antimuscarinic effects should ideally be selected.


  1. Reduction or blocking of the effects of parasympathetic nerves; antimuscarinic effects include dry mouth, difficulty swallowing, blurred vision, confusion, palpitations, constipation, and urine retention.