PTSD - Pharmacotherapy

Text adapted from: "The adult patient with posttraumatic stress disorder," in Psychiatry in primary care  by Francesca L. Schiavone and Ruth A. Lanius (CAMH, 2019).

Some patients prefer pharmacotherapy over psychotherapy, or find pharmacotherapy easier to access for financial or practical reasons (Hoskins et al., 2015). Even with patients who prefer psychotherapy, pharmacotherapy is important for treating comorbidity, mitigating sleep disruption and stabilizing patients whose symptoms are severe enough to prevent them from engaging in psychotherapy (Lange et al., 2000). A wide range of medications have been investigated, with some promising results (see Table 2 below ).

Antidepressants

Selective serotonin reuptake inhibitors (SSRIs) and serotonin and norepinephrine reuptake inhibitors (SNRIs) are considered first-line interventions for PTSD, although only 20 to 30 percent of patients achieve complete remission on these medications (Berger et al., 2009; Hoskins et al., 2015). A small positive effect on overall PTSD severity has been found for SSRIs as a class, specifically for fluoxetine and paroxetine, as well as for the SNRI venlafaxine. Mirtazapine has shown some effectiveness and may be a useful adjunctive treatment for sleep problems (Hoskins et al., 2015).

Atypical Antipsychotics

Atypical antipsychotics are often used to treat PTSD, particularly as adjunctive agents in patients who remain symptomatic after SSRI treatment (Berger et al., 2009). The evidence for various atypical antipsychotics is mixed. The medications with the best evidence are olanzapine, risperidone and quetiapine. Risperidone and quetiapine have shown small positive effects, particularly on intrusion and hyperarousal symptoms.

Prazosin

Prazosin, an alpha-1 antagonist originally approved as an antihypertensive, can improve sleep, reduce nightmares and ease overall severity of PTSD symptoms. However, it may take up to eight weeks to achieve the full effect. Prazosin is thought to reduce adrenergic activity in the central nervous system. The major dose-limiting side-effects are dizziness and orthostasis. There can be a pronounced first-dose phenomenon, but after the initiation period, prazosin does not seem to produce any sustained decrease in blood pressure (George et al., 2016).

In the available literature, prazosin has been initiated at 1 mg nightly, with titration to effect, and a mean daily dose of 3.1–15.6 mg. Women tend to require a lower dose than men. Prazosin is most often given only at bedtime, but some treatment protocols include a daytime dose (George et al., 2016).

Benzodiazepines

Benzodiazepines generally are not recommended for treating PTSD (Berger et al., 2009; Hoskins et al., 2015). They may have some initial effect on anxiety and insomnia, but there are significant concerns about iatrogenic harm. Abuse potential exists, and PTSD is highly comorbid with substance use disorders (Lange et al., 2000). The memory-impairing effects of benzodiazepines are also a concern, particularly when they are used in combination with psychotherapy, which requires memory consolidation to be effective (Berger et al., 2009).

Mood Stabilizers

The evidence for mood stabilizers as a class is weak, indicating some potential benefit, but involving mainly small, open-label studies (Berger et al., 2009).

Naltrexone

There is a small emerging body of evidence for the use of naltrexone to reduce dissociative symptoms in people with trauma. In one small study  of patients with borderline personality disorder, the mean number of flashbacks per day was reduced in patients treated with naltrexone (Bohus et al., 1999). Further research is necessary to generalize these findings.

Cannabis

Patients with PTSD frequently report self-medicating with cannabis, and may seek a prescription for medical cannabis. However, there is not enough evidence to recommend either for or against this use. The potential for harm exists, including increased risk of psychotic symptoms and short-term cognitive dysfunction (O’Neil et al., 2017).

Nabilone, a synthetic cannabinoid, has been discussed as a treatment for PTSD, but the evidence is limited. One small study of male military personnel with PTSD found some improvement in nightmares at doses of 0.5–3 mg (Jetly et al., 2015).

Beta-Blockers

Propranolol has been investigated both as secondary prevention of PTSD in the aftermath of trauma and as a potential treatment for PTSD. There is weak evidence that propranolol can reduce physiological reactions to old and new traumatic memories. It remains unclear, however, if and how propranolol affects the overall course and symptomatology of PTSD (Nader et al., 2013).

In PTSD

• The Primary Care Practitioner Role
• Screening & Assessment
• Diagnosis
• Treatment
  • Pharmacotherapy
• Clinical Tools
• Resources and References