GAD pharmacotherapy beyond SSRIs and SNRIs

Pregabalin has the most substantial evidence among the non-SSRI, non-SNRI options. Multiple randomized trials support it, and the 2019 Lancet network meta-analysis of GAD drug treatments included it among the effective agents. Pregabalin is approved for GAD in Europe. It isn't FDA-approved for GAD in the United States, so its use here for anxiety is off-label. It has a faster onset than SSRIs and doesn't cause the sexual side effects that drive much SSRI discontinuation, but it has its own profile: dose-related sedation, dizziness, and weight gain, plus a controlled-substance status (Schedule V) tied to misuse and dependence concerns, particularly in patients with prior substance use disorder.

Buspirone has older trial evidence in GAD. It doesn't cause dependence or sedation, and it doesn't produce a withdrawal syndrome. Its effect size is modest, and its evidence is specific to GAD rather than to panic or social anxiety. It's often used as an add-on to a partially effective SSRI, or as a primary option when a patient can't tolerate SSRIs.

Hydroxyzine, an antihistamine, has randomized evidence for short-term symptom relief in GAD. It isn't habit-forming. Its main drawback is sedation, and it's generally used for shorter-term or as-needed relief rather than as a long-term primary treatment.

Quetiapine, an antipsychotic, has randomized trial evidence in GAD. Despite that evidence, it's rarely an early choice, because its side-effect burden, including metabolic effects, weight gain, and sedation, is substantial relative to the alternatives. Guidelines generally hold it in reserve.

These medications enter the picture in a fairly consistent pattern: after a first-line SSRI or SNRI has been given an adequate trial, at an adequate dose, for an adequate length of time, and has either not worked or not been tolerated. The choice among them depends on the specific reason the first-line option failed, the patient's other conditions, and the side-effect trade-offs each one carries.

For a shareable, patient-facing explainer of how some of these classes act, including antipsychotics like quetiapine and benzodiazepines, see PsychiatryRx's interactive guide to how psychiatric medications work in the brain. It doesn't cover pregabalin, buspirone, or hydroxyzine.