Nestogen 0-6mos lactose free

as ko lang po if may user dito ng nestogen lactose free.0-6mos ok po sya even mmurahin? mix bf & bonna user c baby pero d kase sya nag ggain ng weight, need nya magswitch to lactose free na milk. option sana is ung pinaka cheap muna, baka ok nman. or if not nestogen, any reco po n lactose free na makakagain kay baby. shes 1 mos old and 1 wik. 3.1 at birth pero 3.5 lng na gain.