Introduction

Company name: Pfizer Limited

Address: Ramsgate Road

Sandwich

Kent CT13 9NJ

Telephone: 0845 300 8034 (Out of hours: 01304 616161)

Fax: 01737 332521

Email: UKVetLine@pfizer.com

Website: www.only4vets.co.uk

Presentation

A clear, colourless solution for injection. Contains detomidine hydrochloride 10 mg/ml. Domosedan contains methyl parahydroxybenzoate 0.1% w/v as a preservative.

Uses

Domosedan is a sedative with analgesic properties used with or without butorphanol to facilitate the handling of horses for examination, minor surgical interventions and other manipulations.

Domosedan is also indicated for use with ketamine for short duration general anaesthesia to carry out surgical procedures such as castration.

Dosage and administration

The following procedure is recommended: Use two sterile needles, one to fill the syringe from the bottle and one to inject the patient. Once the required dose has been withdrawn from the vial, the syringe should be removed from the needle. A separate sterile needle should be inserted into the injection site and the syringe connected to it. The needles should be discarded.

Domosedan alone for sedation

For parenteral use by IM or slow IV injection. Onset of effect is more rapid following intravenous administration.

Dosage table
Anticipated level of sedation	Light	Moderate	Profound
Dosage (IM or IV) mcg/kg	10 - 20	20 - 40	40 - 80
Dose (IM or IV) ml/100 kg	0.1 - 0.2	0.2-0.4	0.4 - 0.8
Commencement of effect (mins)
IV	3	2	1
IM	5	5	5
Duration of action (hrs)	0.5 - 1	0.5 - 1	0.5 - 2
Note these times are approximate and will vary in individual animals.

Domosedan with butorphanol for sedation

Dosage: 0.10 ml Domosedan/100 kg (10 mcg/kg detomidine hydrochloride) intravenously, followed within 5 minutes by 25μg/kg butorphanol (e.g. 0.25ml/100kg of a 10mg/ml solution), intravenously. Clinical experience has shown that 5mg (0.5ml) Domosedan and 10mg (e.g. 1ml of a 10 mg/ml solution) butorphanol affords effective, safe sedation in horses above 200 kg bodyweight.

Doses (ml) for Domosedan/butorphanol sedation and analgesia IV
kg	Domosedan (10mg/ml)	butorphanol (10 mg/ml)
50	0.05	0.10
100	0.10	0.25
150	0.20	0.4
200	0.25	0.5
250	0.3	0.65
300	0.35	0.75
350	0.4	0.9
400	0.5	1.0
450	0.55	1.15
500	0.6	1.25
550	0.65	1.4
Clinical experience has shown that these doses are safe and effective in horses over 200kg
Domosedan 0.5ml, butorphanol (10 mg/ml) 1.0ml

Domosedan and ketamine (short duration anaesthesia)

Ketamine must not be used as the sole anaesthetic agent in horses. To obtain satisfactory surgical anaesthesia, it is important that the following procedure is used:

Administer Domosedan at a dose rate of 20 mcg/kg by intravenous injection.

Allow 5 minutes for the horse to become deeply sedated then administer ketamine at a dose rate of 2.2 mg/kg as an intravenous bolus.

Onset of anaesthesia is gradual, the horse taking approximately 1 minute to become recumbent. In large fit horses recumbency may take up to 3 minutes.

Anaesthesia will continue to deepen for a further 1 - 2 minutes and during this time the horse should be left quietly. Horses regain sternal recumbency approximately 20 minutes post ketamine administration.

The duration of surgical anaesthesia is approximately 10 - 15 minutes and if for any reason it is necessary to prolong anaesthesia, thiopentone sodium can be administered IV in boluses of 1 mg/kg as required. Total doses of 5 mg/kg (five 1 mg/kg increments) have been given. Total doses greater than this may reduce the quality of recovery.

Thiopentone can also be administered (as above regime) if sufficient depth of anaesthesia is not achieved.

The horse should be allowed to stand in its own time. The horse may be ataxic if it stands prematurely and therefore it should be encouraged to remain recumbent.

To facilitate handling and the administration of the induction agents, some horses have received acepromazine by intramuscular injection at a dose rate of 0.03 mg/kg at least 45 minutes before induction of anaesthesia.

Contra-indications, warnings, etc

Before using any combinations consult the contraindications and warnings that appear on the other products' data sheets.

Domosedan

The use of Domosedan in conjunction with sympathomimetic amines is contra-indicated.

Do not use in horses in the last month of pregnancy.

Withdrawal period: 1 day.

The concurrent use of certain potentiated sulphonamides may cause potentially fatal dysrhythmias. Whilst this effect is under investigation it is recommended that potentiated sulphonamides are not administered during sedation with Domosedan.

Intravenous administration should be slow.

Administration of Domosedan may cause benign, reversible cardiac arrhythmia, incoordination of the limbs and sweating. Slight tremor of individual muscles or muscle groups may occasionally be observed.

Domosedan must not be mixed with other products.

Antidiuretic effect is usually observed within 45 to 60 minutes after treatment. The product should not be used in horses with pre-existing AV blocks, with severe coronary insufficiency or chronic renal failure. Careful consideration should be given to administration to animals in shock and to animals with liver or kidney disease.

Horses should not be given water or food before the drug effect has passed.

Domosedan and ketamine

It is always necessary to administer Domosedan prior to ketamine and allow sufficient time (5 minutes) for sedation to develop. The two agents will therefore never be administered simultaneously in the same syringe.

It is recommended that feed should be withheld for at least 12 hours prior to anaesthesia.

Excitable horses are sometimes poor subjects for anaesthesia. It is a prime requisite that the horse should be quietly and carefully handled during the administration of the anaesthetic agents so as to ensure the minimum amount of upset during the induction period. If the horse fails to become sedated following the injection of Domosedan, then ketamine should not be injected and the anaesthetic procedure should be abandoned.

Domosedan/butorphanol combination

Do not use for horses intended for human consumption. Do not use in horses with a history of liver disease. The combination should not be used in pregnant animals or in animals suffering from colic.

Routine cardiac auscultation should be performed prior to use of this combination.

Do not use the combination in horses with a preexisting cardiac dysrhythmia or bradycardia. Mild to severe ataxia may be encountered but clinical studies have shown that horses are unlikely to collapse. Normal precautions should be observed to prevent patient self-injury.

Operator warnings

Wear protective rubber gloves when using this product.

Wash off splashes from the skin and eyes.

In the event of accidental self-administration seek medical advice and show the label and other product literature, but DO NOT DRIVE as changes in blood pressure may be seen.

Domosedan is an alpha 2 adrenergic agonist. Care should be taken to avoid accidental self-injection.

For animal use only. Keep out of the reach of children.

Pharmaceutical precautions

No special precautions for storage. Following withdrawal of the first dose, use the product within 28 days. Discard unused material. Dispose of any unused product and empty containers in accordance with guidance from your local waste regulation authority.

Legal category

POM-V

Packaging Quantities

Multidose containers of 20 ml and 5 ml.

Further information

Where appropriate Domosedan may be used in conjunction with local anaesthetic agents.

Induction of anaesthesia with Domosedan and ketamine has been used prior to maintenance with halothane. Because of the nature of the induction agents, the effects of halothane may be delayed and special care must be taken to avoid overdosage.

Note: When Domosedan is used as a premedication prior to general anaesthesia, it may delay onset of induction.

Marketing authorisation number

Vm 03649/4000.

Marketing authorisation holder

Orion Corporation, Finland.