Heartworm life cycle
Heartworm is spread from dog to dog by mosquitoes. The mosquito injects small larvae into the dog, which over 6–12 months grow into adult worms up to 10cm long. These worms clog up the heart and blood vessels eventually causing death. Treatment is possible if detected early but is expensive and can be risky so prevention is best.
Types of heartworm prevention
Monthly tablets or chews
These drugs are proven, safe and effective and have been the mainstay of treatment up to now. They are given each month preferably on the same date.
- Nexgard Spectra — a tablet that controls heartworm, most intestinal worms and also contains a drug that kill fleas
Monthly topical treatment
These products are absorbed through the skin. Application involves squeezing drops onto the dog’s neck once a month.
- Advocate — as well as heartworm this product also kills adult fleas, some other topical parasites e.g. lice / mites and most intestinal worms.
Yearly injection
This is given once yearly as an injection under the skin.
- Proheart SR 12 injection — controls heartworm for 12 months in adult dogs. In puppies it can be used at 3months of age then repeated at 6months of age then used yearly.
Intestinal worming
Dogs on Advocate or Nexgard only need a tapewormer every 6 months.
All other dogs need an intestinal allwormer i.e. Drontal or Milbemax every 3 months.