Adult night terrors and paroxetine

Abstract

Although rare, night terrors are difficult to treat and a major management problem, especially when accompanied by sleepwalking or other automatic behaviours. Severe injury (sometimes death) during the period of confusion following the rise from bed has been reported, and more frequent attacks lead to serious disruption of sleep, which may impair subsequent daytime functioning and result in psychiatric comorbidity. Night terrors can thus cause severe disability, and effective therapy would be of benefit to patients and their families. There have been reports of treatment with benzodiazepines, imipramine, and longterm psychotherapy, but only benzodiazepines have shown any notable success. Selective serotonin reuptake inhibitors (SSRIs) have antipanic actions and there is some overlap in symptoms of nocturnal panic attacks and night terrors. We report a series of six patients with night terrors, referred for drug treatment because of distressing or dangerous accompanying behaviours, or sleep disruption. All six patients were assessed clinically and by home polysomnography (medilog). All responded to treatment with the SSRI paroxetine (table). In these patients paroxetine was effective in the treatment of longstanding and disabling night terrors and may be as effective as benzodiazepines, although formal comparison is necessary. Two of our patients were having terrors while on benzodiazepines, possibly because of the development of tolerance which does not occur with paroxetine. Other advantages of paroxetine over benzodiazepines is that it treats comorbid or secondary depression and is not a drug of abuse. We suggest that the terror-suppressing action of paroxetine is a direct effect of its ability to increase 5hydroxytryptamine (5-HT) concentrations in the brainstem by blocking reuptake. Terror-like behaviour in animals and man can be readily provoked by stimulation of the periaqueductal grey matter, and this behaviour in animals is suppressed by acute administration of SSRIs and direct-acting 5HT2c receptor agonists. 5HT2c agonists are in clinical development for the treatment of anxiety and depression and it would be interesting to test their efficacy in night terrors. The effects of paroxetine on sleep are known and probably do not contribute to its effect on night terrors. Further evidence that the therapeutic action of paroxetine may be direct rather than through a neuroadaptive mechanism (thought to underlie the antipanic action) comes from the patients who had relapse after stopping treatment. Night terrors recurred rapidly as plasma and brain concentrations of paroxetine fell, and restarting treatment quickly suppressed them again. In one patient the treatment effect seemed dose related. The two cases previously reported to have responded to imipramine also responded rapidly, suggesting a different mode of action to the antidepressant effect. Imipramine also has 5-HT-uptake blocking effects. We found paroxetine to be a safe and effective treatment for disabling night terrors in a small group of patients. The effectiveness of such a selective agent as paroxetine may also suggest a role for decreased central 5-HT function in the aetiology of night terrors.