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Startect (Canada)

This page contains information on Startect for veterinary use.
The information provided typically includes the following:
  • Startect Indications
  • Warnings and cautions for Startect
  • Direction and dosage information for Startect


This treatment applies to the following species:
Company: Zoetis

abamectin and derquantel oral solution

Veterinary Use Only

DIN 02454327

For sheep

Broad Spectrum Anthelmintic

Active Ingredients

Each mL of STARTECT oral solution contains 1.0 mg abamectin and 10 mg derquantel.


STARTECT™ is a dual active oral anthelmintic solution for sheep.

Startect Indications

STARTECT oral solution is indicated for the treatment and control of gastrointestinal nematode and lungworm infections in sheep and their associated diseases.

STARTECT oral solution has shown efficacy against the following gastro-intestinal nematodes, which are frequent causes of clinical disease:

Haemonchus contortus (including inhibited larval stages)

Teladorsagia (Ostertagia) circumcincta (including inhibited larval stages)

Trichostrongylus colubriformis

STARTECT oral solution has also shown efficacy against the following gastro-intestinal nematodes:

Cooperia curticei

Cooperia oncophora

Nematodirus spathiger

Nematodirus filicollis

Nematodirus battus

Strongyloides papillosus

Oesophagostomum venulosum (adult)

Teladorsagia (Ostertagia) trifurcata

Trichostrongylus axei

Trichostrongylus vitrinus

Trichuris ovis

Chabertia ovina

STARTECT oral solution has shown efficacy against the following lungworms:

Dictyocaulus filaria (adult)

A client information sheet is available for guidelines regarding appropriate use of this product.

Dosage and Administration

STARTECT is a ready-to-use oral solution.

The dose for sheep is 2 mg derquantel and 0.2 mg abamectin per kg bodyweight. i.e. 1 mL of product per 5 kg bodyweight.

Dose Rate 1mL/5kg bodyweight:

Bodyweight kg

Bodyweight lbs

Dose mL











































Drench sheep orally, using a drench gun with silicone sealed ‘o’ rings.

Check dose rates and the accuracy of the drench gun before treatment commences.

Do not under- or over-dose. To ensure administration of a correct dose, body weight should be determined as accurately as possible. If animals are to be treated collectively rather than individually, they should be grouped according to their bodyweight and dosed accordingly.

Directions For Use:

Set the dosing gun to deliver the correct dose volume for the weight of sheep to be treated (see figure 1). If animals are batched for dosing it is very important that careful consideration be given to the weight range within each group, to avoid the risk of overdosing smaller animals. A representative sample of animals should be weighed before treatment.

Figure 1

Gently place the nozzle of the drench gun over the back of the tongue and depress the trigger (see figure 2).

Figure 2

Care should be taken to avoid the following practices because they increase the risk of development of resistance and could ultimately result in ineffective therapy:

- Underdosing, which may be due to underestimation of bodyweight, misadministration of the product or lack of calibration of the dosing device.

- Too frequent and repeated use of anthelmintics from the same class over an extended period of time.

Assess bodyweight as accurately as possible before calculating dosage. Suspected clinical cases of resistance should be further investigated using the appropriate tests, (e.g. Faecal Egg Count Reduction Test). Where the results of the test(s) strongly suggest resistance to a particular anthelmintic, an anthelmintic belonging to another pharmacological class and having a different mode of action should be considered.

Accuracy and proper functioning of the dosage device should be checked.


Extremely toxic to horses.

Do not use in other species as severe adverse reactions, including deaths, will occur.


Do not treat sheep under six weeks of age or weighing less than 10 kg as the safety of STARTECT oral solution has not been established.

Care should be taken to not damage the mouth or pharynx when treating sheep.

Do not retreat for 28 days after last treatment.


Treated sheep must not be slaughtered for use as food for at least 14 days after the latest treatment with this drug.

Do not use in lactating ewes producing milk for human consumption.

Keep out of reach of children. Do not eat, smoke or drink while handling the product.

Wear impermeable rubber gloves during use. Avoid ingestion, inhalation and eye and skin contact. Wash hands after handling the product. In case of accidental ingestion, seek medical advice immediately. Show package leaflet or label to the physician. In case of accidental eye or skin contact, wash affected areas thoroughly with running water and seek medical attention if irritation persists.

Adverse Reactions

Mild transient coughing is very commonly reported following drenching.

Overdose: Adverse events have been observed at dosing rates 4.5x that indicated on the label. Signs of toxicity include dullness, depression, incoordination, weakness, decreased gastrointestinal motility and abnormal breathing pattern, recumbency and death. Non-fatal adverse events have been shown to resolve spontaneously.

Clinical Pharmacology

The chemical name of the first active ingredient in STARTECT oral solution, abamectin (a mixture of Abamectin B1a and Abamectin B1b), is:

Abamectin B1a:

(1R,4S,5'S,6S,6'R,8R,12S,13S,20R,21R,24S) - 6' - [(S) - sec - butyl] - 21,24 - dihydroxy - 5',11,13,22 - tetramethyl - 2 - oxo - (3,7,19 - trioxatetracyclo[,8.020,24] pentacosa-10,14,16,22-tetraene)-6-spiro-2'-(5',6'-dihydro-2'H-pyran)-12-yl 2,6 - dideoxy - 4 - O - (2,6 - dideoxy - 3 - O - methyl - α - L - arabino - hexopyranosyl) - 3 - O - methyl - α - Larabino - hexopyranoside

Abamectin B1b:

(1R,4S,5'S,6S,6'R,8R,12S,13S,20R,21R,24S) - 21,24-dihydroxy -6'-isopropyl-5',11,13,22-tetramethyl-2-oxo-(3,7,19-trioxatetracyclo[,8.020,24] pentacosa-10,14,16,22-tetraene)-6-spiro-2'-(5',6'-dihydro-2'H-pyran)-12-yl 2,6 - dideoxy - 4 - O - (2,6 - dideoxy - 3 - O - methyl - α - L - arabino - hexopyranosyl) - 3 - O - methyl - α - L - arabino - hexopyranoside

The chemical structure of abamectin is:

The chemical name of the second active ingredient in STARTECT oral solution, derquantel, is: (1R,3S,5R,7S,12R) - 12 - Hydroxy - 4,4,4',4',12,14 - hexamethyl - 9',10' - dihydro - 4'H - spiro[9,14 - diazatetracyclo[,9.03,7] tetradecane-5,8'-[1,4]dioxepino[2,3-g]indol]-13-one

The chemical structure of derquantel is:

Pharmacodynamic properties:

Derquantel is the first member of the spiroindoles, a novel class of anthelmintics with a different mode of action from existing anthelmintic classes. It acts as an antagonist at nicotinic cholinergic receptors (nAChR). It prevents contraction of somatic muscle in the parasites by blocking ACh-induced activation of cation channels in the muscle cell membrane. This blockade results in flaccid paralysis in nematodes.

Abamectin is a member of the macrocyclic lactone (ML) family of anthelmintics. Abamectin exerts its anthelmintic effect by binding to glutamate-gated chloride (GluCl) channels expressed on nematode neurones and pharyngeal muscle cells. This leads to an increased permeability of the cell membrane to chloride ions with hyperpolarisation of nerve or muscle cells resulting in paralysis and death of the parasite.

Pharmacokinetic properties:

After a single oral administration of STARTECT oral solution, maximum concentrations of derquantel of 108 ng/mL were reached at 4.2 h. The terminal t1/2 of derquantel was 9.3 h and the absolute bioavailability was 56.3%. The maximum concentration of abamectin after oral administration of STARTECT oral solution was 31.1 ng/mL and was reached at 24 h post-dose. The terminal t1/2 of abamectin was 28 h and the absolute bioavailability was 69.7%.

The metabolism of derquantel is extensive and complex. Derquantel undergoes biotransformation to a large number of metabolites over a short time period and as a result, extensive variation in metabolites has been found over tissues and time periods.

Highest concentrations of abamectin were found in liver and fat with much lower concentrations being present in kidney and muscle. By 10 and 14 days the concentrations in many kidney and fat samples were close to or below the limit of detection. Abamectin B1a was the major component in all tissues.

After oral administration, the majority of derquantel is eliminated in the feces and a smaller part in the urine, while abamectin is almost entirely excreted via the feces with elimination in urine being negligible.

Pharmacokinetic studies in sheep have demonstrated that there are no negative interactions between the 2 active principles, derquantel and abamectin, in STARTECT oral solution.


Doses of 0.9 mL/kg and higher have been associated with symptoms of toxicity. Signs of toxicity include dullness, depression, incoordination, weakness, decreased gastrointestinal motility and abnormal breathing pattern, recumbency and death. Non-fatal adverse events have been shown to resolve spontaneously.


Derquantel, a member of the spiroindole class of anthelmintics, is considered to be a mid-spectrum anthelmintic whereas abamectin has a broad spectrum level of activity. However, resistance of nematodes to the macrocyclic lactone class of anthelmintics of which abamectin is a member, is recognized. STARTECT oral solution, a combination product containing both derquantel and abamectin has demonstrated high efficacy (greater than 95% effectiveness) in the treatment of mixed gastrointestinal nematodes in a large number of clinical and field trials. Further, STARTECT oral solution has also demonstrated high efficacy (greater than 95% effectiveness) in trials against strains of certain species of gastrointestinal nematodes known to be resistant to many classes of anthelmintics and to abamectin and derquantel given independent of each other.


Store at a temperature below 30°C. Do not refrigerate. Once broached, product may be stored for 12 months. Store bottles in carton until used. Protect from light. Protect from freezing.

PRESENTATION: STARTECT oral solution is offered in purple bottles of 1L and 5L.

Zoetis and Startect are trademarks of Zoetis or its licensors, used under license by Zoetis Canada Inc.

Zoetis Canada Inc., Kirkland QC H9H 4M7


CPN: 1198548.0

Order Desk:   800-663-8888
Technical Services Canada:   800-461-0917
Technical Services USA:   800-366-5288
Every effort has been made to ensure the accuracy of the Startect information published above. However, it remains the responsibility of the readers to familiarize themselves with the product information contained on the Canadian product label or package insert.

Copyright © 2020 Animalytix LLC. Updated: 2020-10-21