Brief Answer:
Nyquil capsule that are 13 months expired should be discarded.

Detailed Answer:
Hi XXXX
Thanks for writing in to us.

I have read through your query in detail.
Nyquil is a cough medication and contains a mixture of acetaminophen, dextromethorphan hydrobromide and doxylamine succinate liquid.

These medications must be consumed within the expiry date and maximum up to a month after the mentioned date.

Taking it 13 months after it has expired can be hazardous and can cause serious side effects due to decomposition.

Please discard the Nyquil capsules you have and by new ones from the pharmacy.

Hope this answers your question. Please feel free to correct any oversight in my interpretation of your problems and discuss them in detail as per your requirements.

Hope your query is answered.
Do write back if you have any doubts.

Regards,
Dr.Vivek

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