Insomnia is a common complaint in HD.  Clinical studies show that sleep is disordered [Petit 2004] and circadian rhythm (day/night sleep cycle) is disrupted [Morton 2005].  There are no studies testing drug benefit for this problem in HD people.  However, improved sleep and cognition benefit, as well as easier rousability (a measure of apathy) was shown in HD mice when given alprazolam (or Xanax), a benzodiazepine medication [Ramalle-Gomara].

Insomnia Treatments: Though there have been no clinical studies done on treatment benefit, in clinical practice drugs from several classes can improve sleep.  It is important to treat depression and anxiety with SSRI and NSRI antidepressants because these symptoms contribute to insomnia.  Antipsychotic and mood stabilizer drugs can improve sleep but should not be used just for the treatment of insomnia.

Commonly Used Insomnia Medications  

Alprazolam (Xanax®) is a benzodiapzepine medication commonly used. Dosages range from 1-3 mg, with maximum of 4 mg.  Side effects include increased drowsiness on awakening.  Other drugs from this class can also be used.  Daytime use of this drug may cause worsening of depression and apathy.  In HD mouse studies, neither sedation or apathy occurred.  In fact

Trazodone (Desyrel®) is a (non-selective) serotonin reuptake inhibitor that is often used for sleep.  Dosages start at 50 mg and increase to a maximum of 200 mg.  Side effects include dry mouth and constipation.  Serious side effects that are rare include priapism (prolonged erection) and heart arrhythmias.

References

Petit D, Gagnon JF, Fantini ML, Ferini-Strambi L, Montplaisir J. Sleep and quantitative EEG in neurodegenerative disorders. J Psychosom Res 2004 May;56(5):487-96. PubMed abstract

Morton AJ, Wood NI, Hastings MH, Hurelbrink C, Barker RA, Maywood ES. Disintegration of the sleep-wake cycle and circadian timing in Huntington's disease. J Neurosci 2005 Jan 5;25(1):157-63. PubMed abstract

Ramalle-Gomara E, Gonzalez MA, Perucha M, Quinones C, Lezaun ME, Posada-De la Paz M. [Huntington's disease mortality in Spain in the period 1981-2004.] Rev Neurol ;45(2):88-90. PubMed abstract