When to De-worm

Has your pet been "wormed"?  And does that mean he’s been covered with worms? If you’ve been "slimed", you’ve been covered with slime, right? [See "Ghost Busters"]

Most folks mean "de-wormed", or freed of worms when they say "wormed".  They mean that a vermifuge has been administered —  a drug that will cause those worms to flee.  Preferably, we’re talking  a medicine that will just cause the worms to die peacefully, letting them drift gently away with the next regularly scheduled poop. [As opposed to just trying to blow them out, as with arecoline].

As part of your pet’s annual physical examination, we ask you to bring a stool specimen, i.e. about a tablespoonful (use someone else’s spoon) of fresh (less than 12 hours old) poop.  That’s because most intestinal parasites, including worms and protozoa (microscopic one-celled animals), do not pass out where you can see them. They remain inside the intestine eating your pet’s food, or even eating your pet.  Most of the time, when there are parasites inside, they are producing many, many offspring in form of eggs, larvae and oocysts.  These leave the old family homeplace in the intestine with the next bowel movement, going out into the wide world to seek their fortune.

The parasite eggs contaminate the soil wherever an infested animal eliminates. [I started to say, "goes to the bathroom", but if they went to the bathroom and used the toilet, we wouldn’t be having this problem.] Your innocent and delicate pet (the one who likes to eat cat-poo) wanders over this contaminated soil and picks up these microscopic baby parasites.  Some enter the skin directly (like hookworm larvae), others are taken in by mouth.  Eventually, they wind up in the animal’s intestine and set up housekeeping, and the circle of life begins anew [cue inspirational music by Elton John].

Since there’s no one medication that’s guaranteed to eliminate every kind of parasite from your pet with a single dose, we ask you to bring that specimen.  We examine it under the microscope to determine what sort of parasites may be present, thus allowing us to use the most appropriate medicine and use it on the most effective schedule.  The problem is, the parasites are not little precision machines, kicking out a certain number of eggs per minute round the clock.  In fact, one perfectly jolly specimen may contain no eggs at all, while the next reveals the presence of a travelling band of gypsy whipworms.

SO, if the odds suggest that parasites are likely to be present, we may recommend de-worming even when the microscopic examination reveals no evidence of parasites.  For instance, most puppies and kittens have a high likelihood of being infested with hookworms and roundworms.  These nasty things can cause a great deal of damage, even killing the youngster.  Thus, we recommend routine de-worming for puppies and kittens, starting at 3 weeks of age, and repeating at 2-week intervals.  And we haven’t even considered the risk to human health, but you can check it out here.

Another time we may de-worm is when we have intestinal problems that aren’t resolving readily.  It’s worth trying a broad-spectrum de-worming drug just to rule out the parasites, even though you couldn’t find them.

Remember Hunter?  He’s been doing great since recovering from his surgery, that is until this week.  This week he’s been having some diarrhea and occasional vomiting.  He’s also gassing up, somewhat similar to his last episode. Fortunately, he’s not acting nearly so sick, still eating and keeping most of it down.  Here’s a dog who has had numerous negative stool examinations.  He mostly stays inside.  Yesterday he was hospitalized for observation, and the second exam of the day revealed the presence of whipworms.  So in addition to symptomatic treatment for colitis, he’s getting a vermifuge (Panacur – fenbendazole). 

Whipworms get their name from the fact that (provided you use some imagination) they look sort of like Indiana Jones’s bullwhip.  Here’s Max Mobley cracking an 8-foot bullwhip.  Look at the next picture to see the resemblance.   You can’t see it?  What?

Whipworms "sew" themselves into the intestinal lining and suck blood.  They also can cause a lot of inflammation, producing diarrhea and vomiting.  Could they have had anything to do with Hunter’s problem in June?  I don’t know…maybe so.

Sometimes your veterinarian may include de-worming as part of your treatment plan, even though no positive diagnosis of parasites has been made.  Go ahead and do it: it’s safe and doesn’t cost much, and it just might help a whole lot.