 While many medications do not have enough evidence to support their use, three (fluoxetine, paroxetine, and venlafaxine) have been shown to have a small to modest benefit over placebo.With many medications, residual PTSD symptoms following treatment is the rule rather than the exception.Selective serotonin reuptake inhibitors (SSRIs) and serotonin-norepinephrine reuptake inhibitors (SNRIs) may have some benefit for PTSD symptoms.