I'm going to depart from most other moms who've responded so far and really encourage the parents to consider that their daughter might have a reaction to the cow's milk and soy proteins in the formulas they've been giving her (I've even seen this in exclusively breastfed babies who've had major spit up like this as long as the mom is eating dairy and soy, but as soon as she removes it from her diet, the baby stops spitting up, skin gets clearer, sleep improves, etc.). I do not feel that it is normal for a baby to be spitting up that often - I strongly feel that there is almost always a physiological reason for the spitting up.
Also, reflux and allergies can co-exist. Reflux symptoms can greatly improve with the removal of dairy and soy from the baby's diet. Has this 5-month old been given a hypoallergenic or elementa formula that is free from dairy and soy (Alimentum, Nutramigen, Elecare)? If not, that would be my first suggestion is to insist that the doctors let them have a 2-4 week trial on a hypoallergenic formula.
My son was allergic to dairy (cow's milk) and soy via my breastmilk, and he was exclusively breastfed. A friend of mine has a son the same age and exclusively formula fed him, and he too had a dairy and soy allergy (ended up doing well on Nutramigen). The only thing that helped either of our babies was to remove the offending foods from their liquid diets (for me, that meant going dairy and soy free, whereas for her that meant switching formula). Just something to keep in mind... Also, pediatricians tend to under-diagnose infant allergies ("colic" or "reflux" are two common misdiagnoses).
Hope that this little baby girl gets some relief soon from the repeated spitting up... can't imagine that would be too comfortable for her!!!