HELP Please--dog diagnosed with red mange (demodectic )

Question
I have a jack russell he is now 3yrs old as of November.
November of 06 he was diagnosed with demodectic mange.. treated several 100$ later.. then after treatment was done within about 3months (march or april I think) he broke out again- lost his hair, itching, sores etc.  Again he was treated with a stronger medication- the Dermotogisht told us then if it did not work she did not know what to do for him.  Well here we are again and he is Once again broke out.. Please help -  I have researched  and found than using IVOMEC we can possible cure this or at least control it.  Only I have found  dosages to be confusing.  1/10 cc per 10# of body weight I have found.. but not How many times a day/week/ month.. or for how long should he be treated.. I did buy the Ivomec 1% injection medication.I just need to know the Dosages and length of treatment.  Can't seem to get an answer around here  from the Vet's I called.  Can you help me please. We really dont want to loose our pet as we almost did with the first breakout.
Jack (our jack russell) weighs approx 13#'s healthy- maybe close to 10# with the outbreak now.
THANKYOU
Dana

Answer
The dose of Ivomec is 300 - 600 micrograms per pound of body weight orally daily for 60-90 days.  Each 1/10 ml contains 1,000 micrograms.  The minimum dose for demodex is 3/10 ml of Ivomec per 10 lbs.  So you need to figure out what dose you want to use and then multiply that times the weight of the dog to see how much Ivomec to give.