How Do I Know My Dog Have The Mange? How Can I Tell What Kind It Is?

In pets fleas causes hair loss problem and itching. You should give it bath with some good anti-fleas shampoo or soap. "Chiggers" disease also shows such symptoms.
Some antibiotic medicines can work well for this disease so it is better to take your dog to vet for proper medical checkup.

If your dog is losing its hair in patches it most likely is a form of mange and must be taken to the vet. From what I've seen it seems to be very painful.

Whatever type of mange is there, it is caused by mites. Does your dog bites or rubs its itchy areas. If this is the case then it can be Sarcoptic mange. Intense itching creates the swelled crusty ear tips as a first symptom. Hair loss occurs as well. But I think your dog is having Demodectic mange. Its first symptom is hair loss near eyes, lips corner of mouth and the front legs. Its treatment is dips of Mitaban to get rid of agents causing this disease. Keep its bedding separate from other pets. Take it to vet soon if your dog is old enough because old aged dogs have less chances of recovery.