Brief Answer:
you need to take your friend to your nearest ER at the earliest....

Detailed Answer:
Hello XXXX, Welcome to HCM,

Appreciate your concern for your friend,

Now theoretically speaking, 650 mg of 5 tablets should not cause life threatening emergencies as allowance of upper limit of PARACETAMOL is still higher but that being said. there are several other factors also.. most important of them is if the liver function and kidney function is alright / whether or not taken any alcohol or any other drugs with it cause then it'll become quite dangerous and you can never be completely sure of it just by her statement..

To be on the safer side it's always better to take her to your nearest ER for a complete physical check-up , appropriate antidote and Stomach-wash and other therapies as well as a comprehensive toxicology screening and further observation..

Please don't delay any more and take her to your nearest ER at the earliest..

Meanwhile please ensure that she remains alert and sound .. if she's fully alert , you can encourage her to vomit to let as much as possible to get them out of the system and let her drink as much as water she can so that the toxin and drug-metabolites get washed out..

There's no other home-remedies, just follow this advises and it'll be just a matter of time for her to be fine again..

Let me know how she stays in the due course..

Please don't panic and just be vigilant ..

Best Wishes
Kind Regards

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