Secondary Insomnia and the Drugs Used To Treat It
I previously posted about the diagnosis of insomnia, the difference between primary and secondary/comorbid insomnia, and the importance of evaluating for and treating any underlying causes of insomnia. I encourage you to read my Secondary Insomnia post before reading any more of this post. Today I will be talking more about medication treatment options for secondary (comorbid) insomnia.
Although persons with primary insomnia (insomnia not due to an underlying medical or psychiatric disorder) typically do not complain of excessive daytime sleepiness, drowsiness or sleepiness are common symptoms of patients with secondary insomnia. Provigil (modafinil) is a wakefulness promoting agent that acts on a central portion of the brain called the hypothalamus to reduce sleepiness. Because it minimally affects the higher centers of the brain, such as the cortex, it is less likely to cause jitteriness and anxiety than Ritalin and other stimulants. Provigil has Food and Drug Administration (FDA) indications for the treatment of excessive sleepiness (ES) associated with narcolepsy, obstructive sleep apnea/hypopnea syndrome (OSAHS), or shift work sleep disorder (SWSD).
It is important to keep in mind that Provigil is not officially indicated for "insomnia" or "secondary insomnia", that it does not directly treat insomnia but can improve the sleepiness that accompanies many secondary insomnias, and that significant side effects and drug interactions have been reported. Common side effects of Provigil include headache and nausea. It is less likely than the stimulants to raise blood pressure and pulse. The FDA recently warned about Provigil causing hallucinations, suicidal thoughts, mania, and anxiety, though, in my experience these side effects are more common with the stimulants. Rare, potentially fatal, rashes (including Stevens-Johnson Syndrome) have also been associated with Provigil. Provigil can increase or decrease the levels of several medications. The most important drug interaction to be aware of is that Provigil lowers the blood levels of hormonal methods of contraception, making them less effective.
The same hypnotic medications utilized for primary insomnia can also be prescribed for secondary insomnia. However, some of these medications can worsen sleep apnea or underlying lung disease, and caution is indicated if one of these conditions is present. The three primary classes of hypnotic drugs include the benzodiazepines, the benzodiazepine agonists, and the melatonin agonists. The benzodiazepines include Klonopin (clonazepam), Restoril (temazepam), Xanax (alprazolam) and several others. The benzodiazepines can be used treat both anxiety and insomnia. Some of the benzodiazepines, including Restoril, have an FDA indication for the treatment of insomnia. The benzodiazepine agonists include Ambien (zolpidem), Ambien CR, Sonata, and Lunesta. These medications act on a subtype of the benzodiazepine receptor in the brain and are only effective for insomnia, not anxiety. Rozerem (ramelteon) is the only melatonin agonist currently available; it acts on the type 1 and 2 melatonin receptors in the brain to relieve insomnia. Unlike the benzodiazepines and benzodiazepine agonists, Rozerem is not addictive. All of the FDA indicated hypnotics now have a warning regarding "thinking and behavior abnormalities." Sleep-driving, sleepwalking, and sleep sex have been reported with these medications, especially when combined with alcohol. I will write more about the hypnotics in my post about the treatment of primary insomnia in November.
Some secondary insomnias have specific treatments. Alpha-one blockers, a class of blood pressure pills, are fairly effective for the nightmares of Post Traumatic Stress Disorder. Tricyclic antidepressants, including Elavil, are useful for treating the sleep problems associated with Fibromyalgia.