A-28: Endectocidal macrocyclic lactones

Question 1

meaning of endectocides

Answer 1

effective against endoparasites & ectoparasites

Question 2

the 2 main groups of endectocides

Answer 2

Avermectins
Milbemycin

Question 3

drugs belonging to avermecting group

Answer 3

Doramectin
Eprinomectin
ivermectin
selamectin

Question 4

drugs belonging to milbemycin group

Answer 4

Moxidectin
milbemycin oxime

Question 5

method of action of endectocides

Answer 5

acts on arthropodes & nematodes nerve cells, potentiation of inhibitory transmitter: Paralysis (pharynx, body wall & uterus muscles)

Question 6

spectrum of endectocides

Answer 6

immature & mature nematodes
Hypobiotic larvae
microfilariae
arthropodes

Question 7

resistance of endectocides

Answer 7

cestodes
trematodes
cross resistance with Benzoimidazoles & Levamisole
(Ru: GI roundworm
Sus: oesophagostrum
Eq: Strongylys)

Question 8

PK of endectocides

Answer 8

abs: Good, lipophilic
Dist: broad (BBB)
accumulates in fat tissue (BUT residues, WPmeat = 2month)
Moxidectin : WPmilk= 5 ds
Eprinomectin: WPmilk =0 ds in lactating cows

Question 9

Side effects of endectocides

Answer 9

moderatly safe
Abamectin & moxidectin: NOT for CATS & FOALS
safety depends on P-Glycoprotein activity in BBB
(idiosyncratic CNS signs in Murrey grey cattle & Collies)

Question 10

species application of endectocides

Answer 10

SC: sus, Ru
PO: sus (premix), Eq (paste), Ca (tablets only in USA)
Ivermectin: Pour on
Selamectin: Ca & Fe