Overview of Psychotropic Medications and Syndromes

SSRIs

Inhibit reuptake of serotonin at the presynaptic cleft.

Side Effects of SSRIs

GI upset, insomnia, sexual dysfunction, anxiety, weight gain; Serotonin Syndrome (especially if combined with other serotonergic drugs), discontinuation syndrome.

Example SSRIs

Fluoxetine, Sertraline, Paroxetine, Escitalopram, Citalopram, Fluvoxamine.

SNRIs

Inhibit reuptake of both serotonin and norepinephrine.

Example SNRIs

Venlafaxine, Desvenlafaxine, Duloxetine, Levomilnacipran.

Side Effects of SNRIs

Elevated BP, nausea, insomnia, sexual dysfunction; Serotonin Syndrome (especially if combined with other serotonergic drugs), withdrawal syndrome.

Venlafaxine

Blocks reuptake of serotonin and norepinephrine; anticholinergic effects.

TCAs (Tricyclic Antidepressants)

Sedation, weight gain, cardiac arrhythmias, dry mouth, constipation; Serotonin Syndrome (especially if combined with other serotonergic drugs) anticholinergic toxicity, cardiotoxicity in overdose.

Amitriptyline

A tricyclic antidepressant used for depression.

Nortriptyline

A tricyclic antidepressant used for depression.

Imipramine

A tricyclic antidepressant used for depression.

Doxepin

A tricyclic antidepressant used for depression.

Clomipramine

A tricyclic antidepressant used for depression.

MAOIs (Monoamine Oxidase Inhibitors)

Inhibit MAO enzymes, preventing breakdown of monoamines (5-HT, NE, DA).

Phenelzine

An MAOI used for depression.

Tranylcypromine

An MAOI used for depression.

Isocarboxazid

An MAOI used for depression.

Selegiline (patch)

An MAOI used for depression.

Atypical Antidepressants

Includes Bupropion, Mirtazapine, Trazodone, Vilazodone, Vortioxetine.

Bupropion

Norepinephrine-dopamine reuptake inhibitor; insomnia, seizures (dose-related).

Mirtazapine

α2 antagonist and 5-HT2/5-HT3 antagonist; sedation, weight gain.

Trazodone

Weak serotonin reuptake inhibitor, 5-HT2A/2C antagonist, blocks alpha-adrenergic and histamine receptors; sedation, priapism.

Vilazodone

Serotonin reuptake inhibitor and 5-HT1A partial agonist; GI upset, serotonin syndrome.

Vortioxetine

Serotonin reuptake inhibitor and 5-HT1A partial agonist; GI upset, serotonin syndrome.

Benzodiazepines

Enhance GABA-A receptor activity, increasing inhibitory neurotransmission.

Lorazepam

A benzodiazepine used for anxiety.

Diazepam

A benzodiazepine used for anxiety.

Alprazolam

A benzodiazepine used for anxiety.

Clonazepam

A benzodiazepine used for anxiety.

Temazepam

A benzodiazepine used for insomnia.

Buspirone

Partial agonist at 5-HT1A receptors; used for anxiety.

Alpha-2 Adrenergic Agonists

Stimulate central alpha-2 receptors to decrease sympathetic outflow.

Lithium

Modulates second messenger systems, affects sodium/glutamate/GABA.

Mood Stabilizers - Anticonvulsants

Includes Valproate, Carbamazepine, Lamotrigine, Oxcarbazepine, Topiramate.

Atypical Antipsychotics

Block D2 and 5-HT2A receptors; variable histamine/muscarinic/alpha effects.

Typical Antipsychotics

Includes Haloperidol, Fluphenazine, Chlorpromazine, Perphenazine.

Stimulants ADHD Medications

Increase dopamine and norepinephrine by blocking reuptake/enhancing release.

NMDA Receptor Antagonists

NMDA receptor antagonism; enhances glutamate signaling and neuroplasticity.

Non-Stimulant ADHD Medications

Includes Atomoxetine, Guanfacine ER, Clonidine ER, Bupropion.

Serotonin Syndrome

Onset within hours (acute onset) caused by SSRIs, SNRIs, MAOIs, Triptans, Linezolid, MDMA, combinations.

Neuroleptic Malignant Syndrome

Gradual onset (1-3 days) caused by antipsychotics (especially high-potency), dopamine antagonists.

Discontinuation Syndrome

Abrupt discontinuation of SSRIs or SNRIs, occurring days to weeks after stopping or reducing dose.

Neuromuscular Findings in Serotonin Syndrome

Hyperreflexia, clonus, tremor, myoclonus.

Neuromuscular Findings in Neuroleptic Malignant Syndrome

Severe lead-pipe rigidity, bradyreflexia.

Neuromuscular Findings in Discontinuation Syndrome

Mild — chills, diaphoresis possible.

Autonomic Instability in Serotonin Syndrome

Labile BP, tachycardia, profuse sweating.

Autonomic Instability in Neuroleptic Malignant Syndrome

Tachycardia, hypertension, diaphoresis, mydriasis.

Autonomic Instability in Discontinuation Syndrome

Agitation, confusion, delirium.

Mental Status Changes in Serotonin Syndrome

Irritability, anxiety, mood swings, insomnia.

Fever in Serotonin Syndrome

Often > 38.5°C (can be very high).

Fever in Neuroleptic Malignant Syndrome

High (> 38.5°C to 41°C).

Fever in Discontinuation Syndrome

Usually absent or mild.

Key Symptoms of Serotonin Syndrome

Shivering, tremor, diarrhea, hyperreflexia, clonus.

Key Symptoms of Neuroleptic Malignant Syndrome

Rigidity, hyporeflexia, elevated CPK, leukocytosis.

Key Symptoms of Discontinuation Syndrome

Flu-like symptoms, insomnia, imbalance, sensory disturbances.

Diagnostic Clues for Serotonin Syndrome

Hyperreflexia and clonus, rapid onset after serotonergic drug.

Diagnostic Clues for Neuroleptic Malignant Syndrome

Reinstitute drug and taper slowly.

Diagnostic Clues for Discontinuation Syndrome

Recent withdrawal of antidepressant, especially paroxetine or venlafaxine.

Treatment Approach for Serotonin Syndrome

Stop serotonergic drugs, benzodiazepines, cyproheptadine.

Treatment Approach for Neuroleptic Malignant Syndrome

Stop antipsychotics, supportive care, dantrolene or bromocriptine.