My 8 year old daughter was prescribed 12.6 ml twice a day of amoxicillin 400mg / 5 ml suspension twice a day for pneumonia. is this right?

Pneumonia : What is your daughter' weight? Was she very ill, was admitted to a hospital? This seems like a high dose for a pediatric patient. But I don't know the details. Please call her doctor & ask nicely if this dose is the proper dose for yor child's weight & codition. Good luck. I hope she gets better soon.

Hard to say: The drug dose is based both on weight & problem. Without her weight it's hard to make specific recommendations. The estimated 55 lb 8 yo would get 80mg/kg/d with that schedule which is okay for a presumed pneumococcal pneumonia. You might be able to get by with less, but that germ has become more resistant over the past 2 decades.