Since you are run down with the flu and suffering from insomnia, I'd recommend taking a medication that treats your flu symptoms while causing some sedation to help you sleep.
Try tylenol PM (if OK with your doctor), which has benadryl in it and will help you sleep while also treating your aches and pains. There is no narcotic in it, so there is no addictive potential or "hangover". It is not as sleeping pill, but will help nonetheless.
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