What species of cichlid is it???
African cichlids need a very different diet to american cichlids, they need a lot more vegetable matter and more vitamin c etc and less protein. Hole in the head or otherwise known as head and latteral line errosion is usually caused by too much protein and not enough vitamins and minerals in a fishes diet, this is why it is so common in oscars, because people buy oscars and just feed them feeder fish which contain pretty much only empty protein.
So if you have been feeding your african cichlids on a high protein diet made for american cichlids and not a diet which is also high in vegetable matter and wheatgerm, spirulina etc, then this could be a contribution to the disease.
I have also heard that chemical "over-filtration" with carbon etc. can also make the disease worse, because the carbon helps take micro-nutrients out of the water, don't know how true that is though....
In Australia they banned the med that is best for treating HITH (forgotten what its called) because it is also dangerous to humans or something stupid. So I've heard that all you can do here is daily waterchanges to keep the fish in perfect water, and weekly 1/2hr baths in a double dose of Myxazin. HITH is definetly cureable but may take some work....
Goodluck hopefully someone on here has had experience treating HITH with meds and can help you out