Uses

The 10 mg/ml solution is for use in horses not intended for human consumption.

Anaesthetic premedication

Following acepromazine administration, the amount of anaesthetic necessary to induce anaesthesia is considerably reduced. This reduction is approximately one-third of a suitable induction agent.

Tranquillisation

Acepromazine tranquillisation (ataraxy) involves a modification of temperament which is not associated with hypnosis, narcosis or marked sedation. This is achieved with low doses of acepromazine. At low doses acepromazine reduces anxiety, which is beneficial for use in horses prior to shoeing or transportation.

Sedation

At higher dose rates acepromazine is an effective sedative as an adjunct to, or replacement for, physical restraint – e.g. dentistry, handling and shoeing. The relaxant effects aid examination of the penis in horses and the treatment of tetanus and choke.

Acepromazine possesses anti-emetic, hypothermic, hypotensive and anti-spasmodic properties and shows a marked potentiating effect on barbiturate anaesthesia.

Dosage and administration

By intramuscular injection: 0.03 – 0.10 mg per kg bodyweight. Approximately equivalent to 0.15 – 0.5 ml of 10 mg/ml injection per 50 kg (approx. 1 cwt) bodyweight.

By intravenous injection: As for intramuscular, except that it is recommended the injection is made slowly.

Normally single doses of acepromazine are administered.

Long term use is not recommended. On the rare occasions that repeat dosing is required, the dosing interval should be 36 – 48 hours.

Contra-indications, warnings, etc

Take adequate precautions to maintain sterility.

Do not administer to horses intended for human consumption.

Do not administer to breeding stallions. Paralysis of the retractor penis muscle has been associated with the use of parenterally administered acepromazine in horses.

Acepromazine has caused paraphimosis sometimes as a sequel to priapism. When extrusion of the penis occurs, the owner should be advised to inform his veterinary surgeon if retraction of the penis does not take place within 2–3 hours. Suitable treatments have been described in the veterinary literature (see Further Information). When administered to male horses (geldings or stallions), use the lowest dose recommended to produce the required effect.

Do not administer to pregnant mares.

Do not use this product in conjunction with organophosphates and/or procaine hydrochloride, as it may enhance activity and potential toxicity.

Acepromazine is an adrenoceptor blocking drug and this causes hypotension and lowered p.c.v. The product should therefore be administered with great caution and at low dose rates only to debilitated horses and animals in states of hypovolaemia, anaemia and shock, or with cardiovascular disease. Rehydration should precede acepromazine administration. Acepromazine has little, if any analgesic effect so that painful procedures must be avoided, particularly where animals are known to have unpredictable temperaments. Therefore the usual precautions should be maintained when handling sedated horses.

During sedation, horses will normally retain visual and auditory acuity so that loud sounds and rapid movements may cause arousal from the sedated state. It is therefore important to keep treated horses in a quiet environment and avoid sensory stimulation as far as possible.

Tranquillisers are additive to the actions of other depressants, and will potentiate general anaesthesia.

Note

Situations may arise where general anaesthesia is required in the 4–6 hours following use of the product. In such cases, care should be taken to reduce the induction dose of other premedicants and anaesthetic agents, particularly parenteral barbiturates, so as to avoid potentiation and additive depressant effects.

Overdosage

Slow intravenous injection of norepinephrine (noradrenaline) should be used whenever a hypertensive agent is required to reverse any fall in blood pressure.

Epinephrine (adrenaline) is contra-indicated in the treatment of acute hypotension produced by over-dosage of acepromazine maleate, since further depression of systemic blood pressure can result. Other pressoramines such as norepinephrine or neosynephrine should be administered to reverse hypotensive effects. However, the reversing effect of norepinephrine is likely to be transient and repeated doses will normally be required.

Accidental intracarotid injection in horses can produce clinical signs ranging from disorientation to convulsive seizures and death.

Horses should not in any circumstances be ridden within 36 hours of administration of a clinical dose.

For animal treatment only.

In the event of accidental skin contamination, contaminated clothing should be removed and the area washed with copious amounts of soap and water. Medical advice should be sought if irritation persists. In the event of accidental eye contamination, the eye should be flushed with water for at least 25 minutes, holding the eye open. Medical advice should be sought if any irritation or discomfort persists. Care should be taken to avoid exposure.

N.B. Take precautions to avoid accidental injection or self-administration of this potent drug. Should accidental injection occur, seek medical advice immediately. Symptomatic treatment may be necessary.

Pharmaceutical precautions

Do not store above 25°C. Protect from light. Following withdrawal of the first dose, use remainder of the product within 28 days. Discard unused material. When the container is broached for the first time, using the in-use shelf-life which is specified on this package insert, the date on which any product remaining in the container should be discarded should be worked out. This discard date should be written in the space provided on the label. Avoid the introduction of contamination during use. Should any apparent growth or discolouration occur, discard the product.

Keep out of reach of children.

Disposal

Dispose of any unused product and empty containers in accordance with guidance from your local waste regulation authority.

Legal category

POM-V

Packaging Quantities

20 ml glass vials.

Further information

Duration of action may be prolonged and this should be remembered when riding, as acepromazine may affect performance and appear in drug tests for some time. When considering treatment for paraphimosis, the veterinary surgeon may contact the Company. Conservative and therapeutic measures are advised and the following have been recommended in published papers for the treatment of this rare condition:

Manual compression: reduction of the erection by manual compression during the period of general anaesthesia.

Lucke J.N. & Sansom J. (1979) Vet. Rec. 105 July 9 p 21.

Penile support and manual compression: prompt treatment by manual compression or use of an Esmarch bandage has achieved satisfactory results. If priapism occurs following sedation, general anaesthesia has been re-introduced and compression applied immediately.

Gerring E.L. (1981) Vet. Rec. 109 (3) July 18. p 64.

Pearson H. & Weaver B.M.Q. (1978) Equine VetJ. 10 (2) p 85.

Drug reversal: slow intravenous administration of benztropine mesylate produced satisfactory reduction in a gelding.

Sharrock A.G. (1982) Austral J. 58.39.