Gastrointestinal reflux is a condition that affects most babies - their
sphincter at the bottom of the esophagoes we think is just not quite mature.
That is why babies spit up. There is large variation in wether this causes
any problems. Most babies just spit up and the only problem is the need to
change the clothes of those carrying them.  In this case the best treatment
is to have lots of cloth diapers handy. In some babies there is failure to
gain weight, fussiness (from the esophagitis that the reflux can cause - we
think), and perhaps apnea and asthma (The last to tend to be more
controversial).  There are a number of ways to treat this. The simplest
methods are to use the force of gravity to help keep the food down. This
include feeding the baby in a more upright position, keeping them at an
angle of about 30-45 degrees after eating and thickening the feed. For a
formula fed baby, thickening the feed is easy. In the US we used to add rice
cereal to the formula, in Israel they use cornflour. For a breastfed baby it
is a little trickier.  One possiblity is to give a little breastmilk with
the thickener via either bottle (if the kid is past the nipple confusion
stage) or spoon/ syringe whatever and then breastfeed as usual.  For more
serious cases, medications are used. In the US we used bethanecol, Reglan,
here they use ciproside.
 The problem IMHO is that there is alot of over treatment. Parents need to
expect babies to spit up and do laundry. Only if the baby has a problem
should any treatment be considered.  In those cases, treatment can often
dramatically help.