They generally tell you take it at night because a possible side effect is dizziness. Not a problem for me. The usual dosage instruction is to take if at least 30 minutes after a meal. There were four days when I thought I needed more. I took the double dose (after dr consult) and it worked pretty well. Even slept through the night. Now, after a month, I am down to my one trip a night (usually 2-3am) and one time slept through, which I haven't done in years.