Last week I advanced the argument that implementing a treatment regime against worms in dogs and cats based on tablets/oral liquids/ injectables administered as a single dose purporting to kill all the many types of worms may not be the most appropriate way of removing the worm burdens that the animals are carrying.
I maintain that the deworming regime must be aimed at specifically targeting the individual types of worms (or worms belonging to a particular group). There is enough data and empirical evidence, as well as clinic records, which will justify the deduction that “one size does not fit all”. Thus, it is preferable to use a particular drug with its singular set of side effects (all have side effects) against, say, Tapeworms.
Similarly, I recommend a totally different drug, with a specific dosage rate and schedule, to be administered against Heartworms. Specific drugs that target the plethora of Roundworms are also indicated.
A proverbial spanner is thrown into the works when there comes along a “Miracle Drug” which is recommended for broad-spectrum treatment against endo- and ecto-parasites. Ivermectin is such a drug. It truly represents a breakthrough in pharmacology, so much so that researchers (one from Japan and one from the USA) were awarded the Nobel Prize in the early 90s.
This drug is now being used in India as a therapeutic agent of choice against COVID-19. Other countries are implementing this drug within their anti-COVID treatment protocols.
Originally, veterinarians began using Ivermectin in their Large Animal practices as a helpful method to combat ecto-parasites on the skins of cows, horses, etc., as well as against worms within the animals’ bodies. It was only a matter of time before Ivermectin found itself an ally for veterinarians in small-animal practice.
You may ask: “If it is relatively easy to administer Ivermectin to dogs and cats (and hamsters, snakes and stressed caged animals) with some degree of success, then why not implement this anti-parasitic strategy?” since the logic seems solid. Ivermectin, in fact, is currently being used as a major therapeutic against pretty much all worms. And since it can kill ticks, mites, etc., (parasites on the skin’s surface), the Animal Health Assistants, Veterinarians, “breeders” and companion animal owners are all resorting to its use as the drug of choice against ecto- and endo-parasites. Interestingly, the drug can be purchased over-the-counter (for oral or injectable administration) in at least one major livestock supplies establishment in Guyana (which also advertises and markets metal spurs for fighting cocks to lacerate and destroy each other – all illegal).
I am cautioning against equating simplicity of administration with efficacy. I recall that when Ivermectin first emerged on the over-the -counter market, one of my respected colleagues decided to administer it to a litter of puppies. All the pups (Rottweilers, if my memory serves me right) died. It traumatised my colleague. He is made of sterner stuff, and perhaps with my counsel, was able to overcome the trauma of that unwelcome moment in his career. His overall contributions to animal agriculture are immense.
The aforementioned account was provided to reaffirm the extreme importance for practitioners to be trained on the use of certain drugs. They should not be used indiscriminately without acquiring all the information on their use (and this is even more so when the drug is dubbed a “miracle drug”).
My Clinic is perpetually dealing with cases of ill effects from incorrect deworming treatments, not lastly from the use of Ivermectin. It is my conviction that guidance should be sought from competent professionals, who know all aspects of any drug’s usage and the science of that drug’s mode of action, before a decision is made to include any potentially potent drug in a therapeutic or prophylactic deworming regime.
A further issue is the use of Ivermectin against Heartworms in an unprescribed manner. The vet examining your pet will not know if a single administration and quantity has been effective in killing all the Heartworms and their larval stages. What is the optimal interval between applications? The methodology should include doing a microscopic examination of the pet’s blood prior to the first application of Ivermectin, and then again at 2-3 weeks’ intervals.
Regrettably, this is not done, particularly by Animal Health Assistants, who do not have equipment, particularly microscopes. Very few practitioners conduct tests.
I shall discuss this mosquito-borne filarial disease in more detail in future articles. On the issue of deworming, I hope that my detailed discourse on the matter to date has served to illustrate that it is not a “simple” matter. Deworming protocols must be established by trained and competent technicians, applying scientifically-based methods with tested and proven medications.
