Parasites (pharmacology) Flashcards
Ectoparasites
are parasites that live on a host
Endoparasites
are parasites that live in a host
anthelmintic
A drug used to eliminate helminth (intestinal worm) parasites
Examples include ivermectin and pyrantel
vermicides
Paralyzes the worm so the GI tract can expel it.
roundworms
Nematodes and ascarids
Benzimidazoles
A common anthelmintic class
-generic drugs end with the -dazole suffix
Has minimal side effects and is used to treat a variety of parasites in both large and small animals.
When using in food-producing animals, always pay attention to the appropriate withdrawal period.
avermectins
anthelmintic and insecticidal properties
Ivermectin
Is effective as a monthly heartworm preventative in both dogs and cats.
*Treat endoparasites as well as ectoparasites
*Can be used in some exotics
*Collies and other herding breeds may experience seizures when exposed to overly high amounts of ivermectin due to MDR1 gene
*it’s typically dosed in micrograms- be careful to dose correctly .
MDMR1 gene
Multidrug Resistance Genes
Many drugs cause reactions in MDR1 dogs including Imodium, ivermectin, some anesthetics.
Common in herding breeds
Approximately 70% of collies have a defective MDR1 gene
Piperazine
is the active ingredient in a large number of over-the-counter dewormers sold at pet stores. It doesn’t kill worms but paralyzes them (vermifuge) so they are expelled from the body.
Anticestodal drugs
*Used to treat tapeworms.
*Pets can get infected with tapeworm by eating improperly cooked meat or by swallowing a flea that harbors the parasite.
bonus - an example is praziquantel
Antitrematodal drugs
Used to remove flukes from cattle, dogs, and cats.
Some flukes affect the liver and can cause significant damage.
Don’t use in nursing cattle
Antiprotozoal drugs
are used to treat protozoa such as coccidia, giardia, and Babesia
many of the these drugs contain sulfa
–sulfa drugs can cause KCS (Keratoconjunctivitis sicca)
Heartworm disease
*Primarily affects dogs but also affects cats and ferrets.
*Heartworms damage the heart, lungs, and blood vessels in the lungs
*Mosquitoes bite an infected hosts and consume microfilaria (thin early stage of a parasite) and then spread it to the next animal they bite
—-after the microfilaria resides in the mosquito for 14 days). it takes six or seven months after the bite for a dog to develop heartwarm
* the heartworm itself has a bacterial parasite that contributes to the symptoms
giardia
A protozoa causes the diarrheal disease
Resistance to drugs is becoming more common.
If repeated fecals indicate giardia, try another drug or correct the environment.
A vaccine for giardia is available for dogs.
Coccidia
Protozoa
most infections in dogs are not associated with any detectable clinical signs
most common clinical sign of coccidiosis is diarrhea,
can be treated with a variety of drugs, but won’t be controlled unless the environment that fosters it is cleaned up.
Babesia
is a protozoal parasite transmitted by ticks.
signs of Heartworm disease
include coughing, difficulty breathing, and abnormal heart and lung sound in dogs.
Signs in cats are more variable and can include vomiting, coughing, and wheezing.
Heartworm prevention
There are daily or monthly options
In general, puppies should be started on preventatives at six to eight weeks of age.
Periodic testing, every one or two years, is recommended with a monthly preventative.
Fleas
a combination of treating the environment and the pet is the best method for controlling ectoparasites
Note- Shampoos and dips don’t stay active for long periods of time and need to be repeated often in order to continue to be effective.
Pyrethrins
An insecticide
are generally safe for most mammals.
They can quickly kill parasites but aren’t active over longer periods of time.
Carbamates. Edit
Insecticide
act as cholinesterase inhibitors and shouldn’t be used with other cholinesterase inhibitors.
Formamidines,
Are used to treat demodectic mange in dogs.
The SLUDGE syndrome
excessive salivation, lacrimation [tear production], urination, defecation, GI distress, Emesis (vomiting)
caused by an excess of acetylcholine
Insect-growth regulators
IGR
can be added to sprays to help stop the development of fleas into mature forms.
Do not use the dog product which contains
permethrin (i.e., Vectra 3D) on cats or on dogs that live in the same household as a cat.
Parasites
are organisms that live off a host by deriving nutrients and home from their host.
Parasitiasis
– animal is infected but no clinical signs are observed
parasitosis-
animal is infected but clinical signs are showing
Fungal infections
are divided into superficial (skin and eyes) and systemic (blood,lungs, CNS)
