Re: chemotherapy - insomnia
All OTC sleep aids are basicly the same, they contain one of two related antihistamines, diphenhydramine (most of them) or doxylamine (Unisom tablets only)
Taking Tylenol PM, Sominex or Unisom at bedtime isnt habit forming, but the drugs can lose their effect if you take them every night.
Best way to avoid problems is to use them one night, then skip a night, then use them, then skip etc.
Some of the prescription sleeping pills, such as Ambien, have been shown to keep working for months, so it might be worth asking for a trial of one of these
The desire to take medicines is what seperates man from the lower animals - William Ostler
Multiple anecdotes do not equal evidence - Me