Brief Answer:
Give paracetamol, take care of teeth eruption,watch for symptoms

Detailed Answer:
Hi

thanks for the query

I have gone through the query and do understand your concern.
Coming to yor concerns one bybone,starting with inadequate weight gain.
I won't get overly worried for the weight gain as if you follow the growth chart, his weight is appropriate for age.
For fever I would suggest you to give paracetamol (dose is 10 mg/kg/dose)if temperature is more than 100.
Most common cause of fever in this age is some viral infection and fever may be the only symptom during initial one or two days.Symptoms like cough,cold, vomiting or loose motion may develop later.I would request you to watch for associated symptoms and if you are finding any or if fever is of high grade/persistent please consult your pediatrician.
Decreased feeding and mild irritability can be due to fever or teeth eruption. You can massage the gums gently with solution containing local anesthesic agent and antibiotic like clenora gel two to three times a day as it helps is early eruption and also decreases the pain.

I hope this helps.
Please let me know if you have any more doubts.
Regards

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Brief Answer:
Can be used for short term without any complications

Detailed Answer:
Hi

Thanks for follow up

Clenora gel contains cetrimide,choline salicylate and lidocaine and can be used in small amount two to three times a day safely for short term,say 4-5 days when child is more fussy and you think that erupting teeth as a cause.
For long term you can simply massage the gum with milk cream.

Regards

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