SELAMECTIN

(for veterinary information only)

BRAND NAMES: REVOLUTION, REVOLUTION PLUS, PARADYNE

AVAILABLE AS TOPICAL SOLUTION
FOR BOTH DOGS AND CATS

BACKGROUND

Parasite protection for pets is an important concern. We do not want our pets to endure parasitism nor do we want our pets to become a reservoir for human parasite infection. Some type of regular parasite treatment is recommended for all dogs and cats and, of course, there are a multitude of products are available depending which parasites are to be targeted.

Selamectin seems to be an especially excellent choice for outdoor cats as it covers fleas, roundworms, hookworms, heartworm prevention, ear mites, and notoedric mange mites. The addition of sarolaner in RevolutionPlus® had added tick control and doubled up on flea killing power.

In dogs, selamectin covers fleas, sarcoptic mange mites, heartworm prevention, American dog ticks, and ear mites.

HOW THIS MEDICATION IS USED

Selamectin is applied topically on the skin but penetrates to the bloodstream where it acts internally. Because of this, it is waterproof in approximately 2 hours.

Selamectin is labelled for once a month usage, though it is commonly and safely used more frequently in off-label protocols. Selamectin is one of the few parasite products approved for pregnancy and lactation; however, its use is not recommended for patients who are sick, underweight, or debilitated. It may be given to kittens.

If a dose is accidentally skipped, it should be given as soon as it is remembered. Do not double up on the next dose.

SIDE EFFECTS

If selamectin is accidentally consumed orally, it is not toxic but will taste bad, generating salivation and drooling. Vomiting may also result.

Approximately 1% of cats will lose hair at the s.ite of application. If this happens, the hair is expected to grow back but a different parasite product should be considered.

Serious but rarer side effects that have been reported include: seizures, muscle tremors, and appetite loss. The incidence of each of these issues is <0.5%.

In dogs testing positive for the MDR1 mutation, selamectin may cause problems if it is dosed more frequently than once a month. The MDR1 mutation is a genetic defect that alters how medications are transported into the nervous system. It is most common in breeds of collie-type heritage. For more information, click here.

INTERACTIONS WITH OTHER DRUGS

Dogs with the MDR1 mutation may have issues if selamectin is combined with any of the following medications:

Cyclosporine
Spironolactone
Ketoconazole
Itraconazole
Erythromycin
Diltiazem

CONCERNS AND CAUTIONS

Note that selamectin is approved for only one species of tick. If one wants more tick protection for a dog, a different product should be employed.

With regard to heartworm protection, selamectin works retroactively to kill heartworm larvae that have entered the body in the previous month. If a single dose of selamectin is to be used for prevention in the event of travel to a heartworm area, do not apply the product prior to the exposure. Apply it instead within one month following exposure.

Page posted: 11/8/2021