The Hospice Clinician Blog

The FDA has recently approved Silenor for management of insomnia; specifically for insomnia that is characterized by an inability to stay asleep during the night.  Silenor is actually not a new drug. It is the latest incarnation of a drug that has been around for over 40 years, Doxepin. Doxepin is a tricyclic antidepressant drug, similar to Amitriptyline (Elavil) and Nortriptyline (Pamelor). You may be familiar with it by another brand-name, Sinequan. Doxepin, in the form of Sinequan, is approved for the management of depression and has been used for this indication since it’s original release in 1969.

Doxepin has significant sedative effects which may provide some benefit in persons suffering from insomnia if taken at bedtime. The drug has a relatively long elimination half-life of 17 hours which confers a long duration of effect throughout the night. The recommended initial dose of Silenor for insomnia is 6mg at bedtime for adult patients under 65 years of age and 3mg for patients 65 years or older.  In contrast, the doxepin dose for management of depression will usually range from 50mg – 100mg for patients under 65 years of age. Silenor is contraindicated in persons with Glaucoma or Urinary Retention. Both the 3mg and the 6mg strengths seemed to be well tolerated in the clinical trials. The percentage of patients that discontinued Silenor therapy because of adverse effects was similar to that for placebo. Clinicians familiar with Doxepin for depression management generally associate this drug with a relatively high incidence of adverse effects, mostly anticholinergic in nature.  The reasonable tolerability of Silenor observed in the clinical trials for insomnia is likely related to the low doses that are used for insomnia as compared to the much higher doses used for depression. The efficacy of this drug for insomnia compared to placebo was supported by six double-blind studies lasting up to 3 months that included over 1400 patients, aged 18 to 93.  

The cost of Silenor is prohibitive. The cost for the 3mg and the 6mg strengths is the same at $6.60 per dose based upon average wholesale price (AWP).  This works out to about $100.00 for a 15 day supply at 6mg per night. This does NOT compare favorably to one of the most commonly used sedative-hypnotic drugs used in hospice, Temazepam 15mg. The cost of a 15 day course of Temazepam 15mg at bedtime is about $11.00.  Another option available to clinicians would be to consider the use of the old generic Doxepin which is available in the lowest strength as a 10mg capsule. This dosage is slightly higher than the Silenor 6mg, however, the cost differential is huge. A 15 day supply of Doxepin 10mg at bedtime is about $6.50 (a 94% discount off the price of Silenor). There are no studies available comparing the safety and side-effect profile between 6mg and 10mg of Doxepin, however,  we know that this drug has been used safely in doses up to 100mg in the management of depression. I cannot recommend the use of Silenor because of the extremely high cost coupled with the availability of the other cost-effective options mentioned. The selection of 6mg as the dosage of Silenor for insomnia seems arbitrary and is probably more related to economics than therapeutics, given the fact that we already have an inexpensive 10mg doxepin dosage-form available. 

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At Outcome Resources, our goal is to help hospices succeed! Through clinical consultation, reporting, and education programs, Outcome Resources assists hospices of all sizes to focus on best patient care while controlling medication costs. Contact Us or Request an Information Kit to learn more about the benefits available to your hospice through a partnership with Outcome Resources.   

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