Brief Answer:
add paracetamol , cough suppressant and decongestant if needed

Detailed Answer:
HI, thanks for using healthcare magic

Medinex contains diphenhydramine which is an antihistamine that would help reduce some cough/cold symptoms ,additional medication may help.

Medication such as paracetamol/tylenol or ibuprofen would help with the fever and chills along with fluids particularly cold liquids.
The chills are the body's attempt to reset the temperature due to the fever, avoid bundling up though this is the natural response.

If you have a cough and nasal symptoms , an over the counter cough suppressant and decongestant may help .
Dextromethorphan is a cough suppressant

Decongestants would be phenylephrine or pseudoephrine .

If the cough gets wet, then a mucolytic to help break up the mucus would be needed eg guaifenesin, mucomyst, bisolvan

I hope this helps, feel free to ask any other questions

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