1) To determine if medication help extreme preterm infants to tolerate feeding better by reaching full feeding earlier.2) Out of two medication; which one is better for efficacy 1) Erythromycin 2) Metoclopramide. Infants who meet inclusion criteria would be entered to study after parental consent. Infant would be blinded to care givers. Infants will be randomized to receive one of three medication for 7-14 days. If infants fail on one medication they will be allowed to crossover to other medication. Infant would be allowed to treat like other infants. Blindness can be broken if deem necessary by attending neonatologist.