Brand: PARAMECTIN ® Pour-on
PARASITES CONTROLLED* (spectrum of activity)
* Country differences may apply: read the product label!
- Gastrointestinal roundworms: Adult worms and immature stages of Ostertagia ostertagi (incl. inhibited larvae), Haemonchus placei, Trichostrongylus axei, Trichostrongylus colubriformis, Cooperia oncophora, Cooperia punctata, Oesophagostomum radiatum, Oesophagostomum venulosum, Nematodirus spathiger, Trichuris spp, Strongyloides papillosus.
- Lungworms: Dictyocaulus viviparus.
- Sucking & biting lice: Haematopinus eurysternus, Linognathus vituli, Solenopotes capillatus, Bovicola (Damalinia) bovis.
- Cattle ticks (Boophilus microplus) and
- Buffalo flies (Haematobia irritans exigua).
- Residual effect:
- 1 ml product/10 kg (in New Zealand 1ml/20 kg), equivalent to: abamectin 0.5 mg/kg bw.
- LD50 (acute oral) in rats: a.i. 10 mg/kg
- LD50 (acute dermal) in rats: abamectin: a.i. 330 mg/kg
- Estimated hazard class according to the WHO: not applicable for veterinary medicines
Suspected poisoning? Read the article on abamectin safety in this site.
Withholding periods (=withdrawal times) in days for meat & milk (country-specific differences may apply: read the product label)
- Meat: Australia 30 days (ESI 42 days)
- Milk for human consumption: NIL (Zero days).
WARNING !!!: Never use on humans, dogs or cats
You may be interested in the following articles in this site dealing with the general safety of veterinary products:
- Safety for humans
- Safety for domestic animals
- Safety for the environment
- Hazard classifications of pesticides
Risk of resistance of gastrointestinal roundworms to macrocyclic lactones (incl. abamectin): YES, reported in cattle in numerous countries particularly in the following worm species: Cooperia spp and Ostertagia spp.
Resistance of gastrointestinal roundworms to macrocyclic lactones (incl. abamectin) in sheep, goats and cattle has been reported almost worldwide, including the USA, UK, Australia and New Zealand. Based on the very abundant and frequent use of ivermectin and other macrocyclic lactones (with cross-resistance to ivermectin) in livestock it must be assumed that resistance of these roundworms to this chemical class will continue spreading and strengthening in the future.
- Benzimidazoles, e.g. albendazole, febantel, fenbendazole, oxfendazole, etc. Similar or even worse resistance problems than ivermectin
- Imidazothiazoles, mainly levamisole. etc. Similar or even worse resistance problems than ivermectin
- Nitroxinil (limited spectrum of activity)
- Tetrahydropyrimidines, e.g. morantel, pyrantel (limited spectrum of activity)
- Salicylanilides, e.g. closantel (limited spectrum of activity)
These alternative products may not be available in all countries, or may not be available as pour-ons.
This means that if this product does not achieve the expected efficacy against the mentioned parasites, it may be due to resistance and not to incorrect use, which is usually the most frequent cause of product failure.
Are the active ingredients of this product ORIGINAL* or GENERICS**?
*Meaning that they are still patent protected and generics are not yet available
**Meaning that they have lost patent protection and may be acquired from manufacturers of generic active ingredients other than the holder of the original patent.
COUNTRIES where this brand/product is marketed: Australia, New Zealand (different composition -1% - but same dose)
GENERIC BRANDS available? Yes abundant in Australia and New Zealand, not in the USA or Europe.
Click here to learn more about GENERIC vs. ORIGINAL drugs.
For an overview on the most used antiparasitic pour-on brands click here.
Abamectin, one of the first macrocyclic lactones developed, was introduced already in the 1980s (by MSD AGVET). As all macrocyclic lactones, abamectin is an endectocide, i.e. it is simultaneously effective against external parasites and against internal parasites (mainly roundworms). As for other macrocyclic lactones, abamectin has no efficacy whatsoever against tapeworms and flukes. It is considered as the "cheap" ivermectin, with a similar spectrum of efficacy but less potent and slightly more toxic. Abamectin is vastly used in agricultural and hygiene pesticides worldwide, also in Australia. Interestingly, abamectin it is only marginally used in veterinary products in the USA and Europe.
It is useful to know that pour-on administration of parasiticides has some disadvantages when compared with injectables and drenches. In several scientific studies it has been shown that ivermectin administered as a pour-on is not "automatically" absorbed through the skin. Licking (self licking or licking of other treated animals) may account for >50% of the total intake, compared with only about 10% absorbed directly through the skin. This is the reason why a dose of 500 mcg/kg bw is needed after pour-on treatment, compared with only 200 mcg/kg bw after injection. And it has been also shown that intake of topically administered active ingredient in some cattle may be twice as high as in other ones, all treated at the same rate. The reason is that individual cattle show a different licking behavior. An important practical consequence is that the quantity that is finally ingested and is therefore available for the control of gastrointestinal worms depends on the licking behavior of the treated animals. "High lickers" can be overdosed, whereas "low lickers" can be underdosed. And chronic underdosing of animals in a herd may enhance development of resistance to ivermectin and other macrocyclic lactone in gastrointestinal roundworms.
To our knowledge similar studies have not been carried out with abamectin pour-ons, but it must be assumed that the licking-behavior of cattle affects intake of abamectin in a comparable way. A similar effect of the licking behavior on the intake of active ingredient after pour-on administration has also been shown for fluazuron, a tick development inhibitor.
Absorption through the skin is also negatively affected by the thickness of the skin and the hair coat, by dust and mud on the coat, by product lost on fences and yards, etc, factors that don't play a role after injection. The pour-on formulation should not be administered to wet animals, and rain shortly before (up to 6 hours) or after administration can cause product run-off and thus under-dosing. The pour-on shouldn't be administered by strong winds that may blow away part of the product and/or contaminate the workers.
This article IS NOT A PRODUCT LABEL. It offers complementary information that may be useful to veterinary professionals and users that are not familiar with veterinary antiparasitics.
Information offered in this article has been extracted from publications issued by manufacturers, government agencies (e.g. EMEA, FDA, USDA, etc.) or in the scientific literature. No guarantee is given on its accuracy, integrity, sufficiency, actuality and opportunity, and any liability is denied. Read the site's DISCLAIMER.
In case of doubt contact the manufacturer or a veterinary professional.