Published online by Cambridge University Press: 12 March 2019
The association of sleep disorders and post-traumatic stress disorder (PTSD) is almost universal. Nightmares are not only one of the most commonly associated but also featured as a diagnostic criterion for PTSD. PTSD-related nightmares are particularly distressing, may impair functioning and increase risk of suicide. No specific pharmacologic agent has been demonstrated to impair dreaming. Inhibition of PTSD-related nightmares with pramipexole has not heretofore been described. Such a case is presented.
Case study - This 60 year-old male with PTSD and trauma-related nightmares upon introduction of pramipexole 0.5mg PO qHS for Restless Leg Syndrome (RLS) had total elimination of dreams, which recurred upon discontinuation of this agent as a result of insomnia and increased anxiety. A lower dose of 0.375mg qHS provided optimal RLS-symptom control and overall improved tolerance despite nightmare recurrence.
Abnormalities on Neurological examination: Recent recall: 2 of 4 objects without improvement with reinforcement. Able to spell the word “world” forwards but not backwards. Abstract thought impaired. Chemosensory testing: Anosmia and normogeusia. Motor: Drift: mild right pronator drift with right cerebellar spooning and right abductor digiti minimi sign. Reflexes: 3+ brachioradialis and biceps bilaterally, absent ankle jerks. Other: CT scan with and without contrast: normal.
Nightmares related to PTSD may occur during Rapid Eye Movement (REM) sleep and non-REM sleep. Underlying sympathetic activation may lead to disruptive motor behavior similar to that seen in REM sleep behavior disorder. The exact mechanism of action by which inhibition of dreams occurred with use of pramipexole is unclear. Such a response is consistent with prior documented evidence of REM sleep suppression with low-dose pramipexole such as it‘s efficacy in reducing the intensity and frequency of nightmares and dream enactment related to REM sleep behavior disorder. Further research on therapeutic interventions that target nightmares directly may be beneficial for the management of patients with PTSD.