heartworm prevention for a heartworm positive dog

There is no Imiticide in Korea to treat the adult heartworms.  According to the vet, there is a shortage worldwide.  He does not expect the medicine to be available until December at the earliest.  He wants me to put her on Heartguard Plus until she can be treated for the adult worms.  I've always heard that this was a "no-no" for heartworm positive dogs.  Please advice.  Thanks for your time and have a good day.

[Aleda M Cheng, D.V.M., C.V.A]

Treatment with the antibiotic: doxycycline at a dose of 10mg per Kg of body weight for one month or more and monthly Heartgard Plus is a recognized treatment to help eliminate immature heartworms from your dog's heart and circulatory system.  By killing off immature heartworms there will be fewer adults in your dog's system by the time the Immiticide becomes available.  

The doxycycline antibiotic weakens the adult heartworm by killing Wolbachia, which is a symbiotic parasite inside heartworms.  When Wolbachia is killed by doxycycline it causes female heartworms to be unable to reproduce, thus decreasing the burden of heartworms.  Wolbachia is also responsible for the adverse effect of heartworm treatments.  

Doxycycline and Heartgard are relatively safe treatments and can be used until the Immiticide becomes available again.  A low dose of steroids can also be added to eliminate or decrease any possible adverse side-effects.