"i have been taking ambien or zolphidem for almost 15 years. i had horrible insomnia where i couldn&#039;t sleep sometimes at all during the night. the insomnia went on for about 2 years before i tried ambien. it worked immediately.  i don&#039;t take it every night and when i do i break off a third of the pill. the only side effect is sometimes grogginess in the morning. i worry about a little memory loss. i was told it disrupts your rem sleep which can affect memory. trying to get off completely but don&#039;t want to go through that horrible insomnia again."