I've 18month old baby girl with poor appetite.i wld like to give medicine .what is best with good effect ?

Get evaluated: Some children have extensive food allergies. They may have a poor appetite with failure to thrive and low weight because of allergies to some of the foods they are eating. If it is a longstanding problem or is worsening, make an appointment with your pediatrician to discuss it. They may need to see a peds GI physician.

Watch fluids: Most 18 month olds eat one meal a day. If she is growing well, then i wouldn't worry. Make sure she is not filling up on fluids instead of eating. If she eats one particular meal, offer lots of fruits and veggies for that meal. If she isn't growing well, then her doctor can help. No medicines needed.

Picky eaters: Picky eating habits will drive most parents crazy.At 1.5 yr the grow rate has slowed to ~5lb/3inch/yr which is much slower than earlier.Feeding matches need. Most feed well 4days a month ; nibble the rest.Single item days are common(breads, vegies, etc) ; a balanced week is more common than a balanced meal. If you only offer nutritious choices, they will get what they need.Discuss with your dr.