You do have to be careful with insomnia - sometimes it is a side effect of sleep apnea. Some other signs are sleepy/drowsy during the day (go figure), snoring, waking up throughout the day, stop breathing while sleeping (this is what wakes you up although most do not realize it and assume it must have been some noise), change in mental ability - ie concentration, perfomance of work, walk and chew gum at same time, do not dream, wake up feeling just as tired or even more tired, personality changes are common - the good time person becomes a grump, etc. Sufferers of sleep apnea of course have an elevated risk of having accidents (fall asleep at the wheel), family issues as they are always drowsy and fall asleep for short periods during the day due to exhaustion from lack of proper sleep.
If apnea is not a problem then a recommend a good round of sex - always worked for me.