Contraindications
Do not use on fish with infectious diseases, as treatment against sea lice may aggravate the clinical signs and increase mortality.
Adverse reactions
The fish tend to move closer to the surface during treatment and increased restlessness and jumping frequency are observed. Occasional mortalities have also been observed after treatment with the recommended treatment regimen. Miscalculation of the treatment volume (overdosing), extended exposure of treatment period or low water temperature may increase the frequency of adverse reactions or signs of intoxication.
Special warnings for target species
At water temperatures below 6°C, the product's safety margin is reduced. Extra precautionary measures should be exercised if treatments are performed at low water temperatures. The efficacy of this medicinal product declines with water temperatures below 6°C. Lack of efficacy and reduced sensitivity to deltamethrin has been observed. Suboptimal treatment regimen and frequent treatments as well as the use of pyrethroids only for sea lice treatment, can induce reduced sensitivity in the sea lice with lack of efficacy as a possible consequence.
The risk of intoxication may increase in fish with severe skin lesions.
Symptoms of overdosing are equilibrium problems, behavioural disturbances, gasping for air in the water, alteration in pigmentation and mortalities. If any of these symptoms occur, the treatment should be terminated and unmedicated sea water let in. If the fish are treated in a raised net enclosed in a tarpaulin, the tarpaulin should be removed and the net released to normal depth immediately. In order to speed up water exchange in the treatment unit such cases, an artificial water-current can be applied (e.g. by using a boat motor propellor).
The acute toxicity of deltamethrin in fish is high. The toxicity is affected by the dose, exposure period and the water temperature. Signs of intoxication have been seen in laboratory trials with doses 5 times the recommended dose at 30 minutes exposure and doses 3 times the recommended dose at 60 minutes exposure. Experience from clinical use of the product indicates that lower doses and/or other exposure conditions may also cause signs of intoxication.
Use in broodstock
Use only in accordance with the benefit/risk assessment by the responsible veterinarian because reproductive toxicity has not been established in the target species.
Environmental precautions
The substance is toxic to crustaceans and should not be used in sea farms where crabs or lobsters are kept in close vicinity of the treated sea-cages (<200m), or when local water currents increase the likelihood of exposure.
To prevent toxic effects on local aquatic organisms and to prevent toxic waste of deltamethrin to be washed into the littoral zone, bath treatment should be performed on an outgoing tide, or during periods with a local outgoing current.
Incompatibilities
In the absence of compatibility studies, this veterinary medicinal product should not be mixed with other veterinary medicinal products.
Withdrawal period
5 degree days for treated Atlantic salmon. 5 degree days for treated Rainbow trout.
Operator warnings
Wear protective clothing (i.e. cotton overalls and nitrile rubber or neoprene gloves (0.3mm thick)) and disposable face mask when handling the product, tarpaulins and nets of treated cages.
Avoid contact with the skin, eyes, nose and mouth. If clothing becomes contaminated remove without delay and wash skin thoroughly with soap and water. Change out of protective clothing and wash hands thoroughly after using the product. Launder protective clothing before re-use.
Do not smoke, eat or drink when handling the product.
The product is of low hazard by oral and dermal routes. Inhalation of the product may cause irritation to the mucous membranes and respiratory tract. Skin exposure may cause transient sensations (tingling, numbness), which disappear after a few hours. Obtain medical advice if symptoms persist.
All equipment that has been in contact with the product should be thoroughly cleaned after completion of treatment.
The product may cause harm to the unborn child. Pregnant women should therefore be extra careful when handling the product.