NAC is a glutamate modulator derived from the amino acid cysteine. It’s been tested in many psychiatric conditions, but shows the most promise as an adjunctive treatment to selective serotonin reuptake inhibitors for compulsive behaviors like obsessive-compulsive disorder (OCD), trichotillomania, nail biting, and skin picking. Evidence is modest but encouraging.

When a benzodiazepine is appropriate for use (short term; minimal risk of abuse), we consider lorazepam to be a first-line agent.

Flurazepam is an older benzodiazepine that has fallen out of favor due to its very long half-life and its active metabolites.

Diazepam is a long-acting benzodiazepine useful for anxiety, alcohol withdrawal, muscle spasms, and seizures. 

Alprazolam is fast acting and effective for generalized anxiety disorder (GAD) and panic disorder, but its short duration of action may contribute to breakthrough symptoms between doses and make withdrawal more difficult.

Valbenazine was the first of the vesicular monoamine transporter inhibitors to be approved for the treatment of tardive dyskinesia (TD) in 2017.

Trihexyphenidyl is an anticholinergic medication that is less favored than benztropine because it must be dosed three times daily and is only available in oral formulations. 

Tetrabenazine was the original vesicular monoamine transporter inhibitor brought to market and approved for the treatment of Huntington’s disease.