Tetracyclic antidepressants 

Tetracyclic antidepressants contain four cyclic rings as part of their structure. Tetracyclic antidepressants are similar to tricyclic antidepressants and act by inhibiting reuptake of neurotransmitters serotonin and/or noradrenaline in the brain, and elevate mood. They are effective antidepressants but are used less often now due to their side effect profile.

Tetracyclic agents include: Mirtazapine (Remeron). Maprotiline (Ludiomil).Amoxapine (Asendin; amoxapine is sometimes classified as a tricyclic).

The drugs work differently in the brain. Tricyclics and tetracyclics affect the norepinephrine and serotonin levels in your brain, while SSRIs only affect serotonin. This means that TCAs can cause more side effects than SSRIs. Tricyclic antidepressants are also more dangerous if you overdose with them.

Tetracyclics are cyclic chemical compounds that contain four fused rings of atoms, for example, Tröger’s base. Doxycycline, a tetracyclic antibiotic. Mirtazapine, a tetracyclic antidepressant.

Tetracyclic antidepressant toxicity may cause disorientation, severe drowsiness, memory impairment, tachycardia or bradycardia, arrhythmias, restlessness, agitation, seizures, loss of muscle coordination, stupor, shortness of breath, hypotension, vomiting, sweating, urinary problems, and coma.