Interesting--don't know exactly why this thread showed up--even the last post is from May of 2016.
Story is still pretty much the same--Novartis only sells Interceptor (single purpose product-heartworm--well, and round worm, hook worm and whipworm, only outside the USA. They manufacture and sell Sentinal--heartworm (the the three other worms) and internal (not entirely effective) flea control. Sentinal Plus--heartworm, round worm, hook and whip worm the same not terribly effective flea control and tapeworm control. There are also other manufacturers who sell heartworm controls that use milbimycin (Trifexis and at least one other but you'll have to do a Google search 'cause I can't remember the name of the other one. Trifexis is still the most expensive combo product where the heartworm control is milbimycin.
I've been able to get Interceptor again...
Richter & Sypha
Glengate's Mountain Fortress CAA ORT L1V NW1 L1I L1E L1C NW2 L2V L2I ACT1 RATI SOG WAC
& Sirai's Golden Masquerade ORT NW1 L1C L1V L1E L1I NW2 RATI SOG WAC
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