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

An aqueous solution for injection of medetomidine hydrochloride. Each ml contains medetomidine hydrochloride 1.0 mg.

Uses

Dogs

For restraint, sedation and analgesia associated with clinical examinations and procedures, minor surgery and pre-anaesthesia.

As a premedicant before thiopentone, halothane general anaesthesia and as a premedicant before general anaesthesia with propofol.

In combination with butorphanol for sedation, analgesia and as a premedicant to thiopentone anaesthesia.

Cats

For restraint and sedation.

In combination with ketamine for induction of general anaesthesia prior to surgical procedures in the cat.

In combination with butorphanol for sedation and analgesia, and combined with both butorphanol and ketamine for general anaesthesia.

As a premedication before alphaxalone/alphadolone for general anaesthesia.

Dosage and administration

DOGS

Domitor alone for canine sedation and analgesia

For parenteral use by intramuscular (IM), intravenous (IV) or subcutaneous (SC) injection.

Animal	Dose micrograms/kg	Effect	Quantity
Dog	10 - 30	Slight sedation	0.1 - 0.3 ml/ 10 kg
Dog	30 - 80	Moderate to deep sedation and analgesia	0.3 - 0.8 ml/ 10 kg
Dog	10 - 20	Pre- anaesthesia	0.1 - 0.2 ml/ 10 kg

Maximal effect is obtained within 10 - 15 minutes. Duration of the clinically useful effect is dose related (30 - 180 minutes). The dose can be repeated if necessary.

Domitor with butorphanol for canine sedation and analgesia

Domitor and butorphanol can be administered together in the same syringe, by IM or IV injection.

Dose rate: 10-25 mcg/kg ( 0.01 - 0.025 ml/kg) Domitor, depending on the degree of sedation required, plus 0.1mg/kg butorphanol (0.01ml/kg of 10mg/ml solution). Allow 20 minutes for sedation to develop before commencing the procedure.

Reversal with an equal volume of Antisedan IM to that of Domitor used results in sternal recumbency approximately 5 minutes later and standing approximately a further 2 minutes later.

Domitor with butorphanol followed by thiopentone anaesthesia

Dose rate: Domitor 10 mcg/kg (0.01 ml/kg) and butorphanol 0.1mg/kg (0.01ml/kg of 10mg/ml solution).

Domitor and butorphanol can be administered together in the same syringe, by IM or IV injection.

Allow 15 minutes for sedation to develop before administering thiopentone.

Antisedan administered in the post-operative phase will hasten the recovery from anaesthesia.

Domitor as a premedicant before thiopentone in dogs, anaesthesia being maintained with halothane (with or without nitrous oxide)

Domitor is administered at least 20 minutes before thiopentone (induction agent) to allow sedation to develop. Domitor may be administered at a dose rate of 10, 20 or 40 mcg/kg (0.01, 0.02 or 0.04 ml/kg). Subsequent guideline doses of thiopentone would be 6.9, 4.5 and 2.4 mg/kg respectively (e.g. 0.276, 0.18 or 0.096 ml/kg of 2.5% solution). However, the dosage required may vary considerably in individual animals. The optimum dose of Domitor is in the range of 20 - 40 mcg/kg and will depend on the temperament of the dog. At higher doses, thiopentone may not be required for intubation, i.e. intubation may be possible under medetomidine alone.

Canine doses (ml) for mild sedation, or premedication prior to thiopentone, IM or IV:
	Domitor 1mg/ml	butorphanol 10mg/ml
kg	10mcg/kg	0.1 mg/kg
1	0.01	0.01
3	0.03	0.03
5	0.05	0.05
10	0.10	0.10
15	0.15	0.15
20	0.20	0.20
25	0.25	0.25
30	0.30	0.30
40	0.40	0.40
Canine doses (ml) for deep sedation:
	Domitor 1mg/ml	butorphanol 10mg/ml
kg	25 mcg/kg	0.1 mg/kg
1	0.03	0.01
3	0.08	0.03
5	0.13	0.05
10	0.25	0.10
15	0.38	0.15
20	0.50	0.20
25	0.63	0.25
30	0.75	0.30
40	1.00	0.40

Domitor		Thiopentone
Dose in mcg/kg	Quantity in ml/10 kg	Dose in mg/kg	ml/ 10kg of 2.5% solution
10	0.1	6.9	2.76
20	0.2	4.5	1.8
40	0.4	2.4	0.96

Thiopentone as a dilute solution (1.25 - 2.5%) is administered by the IV route slowly to effect over a period of 30 - 45 seconds. Once jaw relaxation is considered adequate, tracheal intubation can be undertaken.

N.B. Onset of unconsciousness may be delayed for up to one minute following injection of thiopentone. Therefore, slow IV injection is required as indicated above.

After intubation, anaesthesia may be maintained with halothane in oxygen (with or without nitrous oxide) administered to effect. Recovery from anaesthesia may take from 20 to 60 minutes.

Food should be withheld for 12 hours prior to anaesthesia.

For recoveries in excess of one hour it is advisable to administer Antisedan.

Domitor as a premedicant before propofol in dogs.

Domitor is administered either IV at least 10 minutes before propofol (induction agent), or IM at least 20 minutes before propofol to allow sedation to develop. Domitor may be administered at a dose rate of 10, 20 or 40 mcg/kg (0.01, 0.02 or 0.04 ml/kg). The following table is a guideline for doses of Domitor and propofol:

Domitor		Propofol
Dose in mcg/kg	Quantity in ml/10 kg	Dose in mg/kg	Quantity in ml/10 kg of 10mg/ml emulsion
10	0.1	1.5	1.5
20	0.2	1.1	1.1
40	0.4	1.0	1.0

Following premedication with Domitor, doses of propofol of up to 4 mg/kg (e.g. 0.4ml/kg of 10mg/ml emulsion) have been safely used when a greater depth of anaesthesia is required.

N.B. The induction time is increased following Domitor premedication; propofol should be administered slowly and up to 2.5 minutes should be allowed before a further dose is given.

Once jaw relaxation is adequate, tracheal intubation can be undertaken. It is advisable to administer oxygen during anaesthesia. For maintenance of anaesthesia the dose of propofol is markedly reduced by medetomidine premedication. Infusion doses of 0.06 to 0.35 mg/kg/minute (e.g. 0.006 - 0.035ml/kg of a 10mg/ml emulsion) will provide stable anaesthesia for dogs sedated with between 40 and 10 mcg/kg Domitor respectively. For intermittent bolus administration, a dose of 1 mg/kg (e.g. 0.1ml/kg of a 10mg/ml emulsion) at intervals of between 4 and 12 minutes will provide stable anaesthesia.

Recovery from anaesthesia may take from 20 to 60 minutes.

Food should be withheld for 12 hours prior to anaesthesia.

Antisedan administered in the post-operative phase will hasten the recovery from anaesthesia.

CATS

Domitor alone for feline sedation and analgesia

For parenteral use by IM or SC injection.

Animal	Dose mcg/kg	Effect	Quantity
Cat	50 - 100	Moderate sedation	0.25 - 0.50 ml/5 kg
Cat	100 - 150	Deep sedation	0.50 - 0.75 ml/5 kg

Maximal effect is obtained within 10 - 15 minutes. Duration of the clinically useful effect is dose related (30 - 180 minutes). The dose can be repeated if necessary.

Domitor with butorphanol for feline sedation and analgesia

Domitor and butorphanol can be administered together in the same syringe, by IM or SC injection.

Dose rate: Domitor 50 mcg/kg (0.05 ml/kg), depending on the degree of sedation required, plus 0.4mg/kg butorphanol (0.04ml/kg of 10mg/ml solution).

Local anaesthetic infiltration should be used for wound suturing.

Reversal with half the volume of Antisedan to that of the previously administered Domitor (i.e. 125mcg/kg ; 0.125 ml/ 5kg) of Antisedan results in sternal recumbency approximately 4 minutes later and standing approximately a further 1 minute later.

Domitor with ketamine for feline anaesthesia

Domitor and Vetalar or Ketaset (ketamine) are administered concomitantly, in the same syringe, by the IM route. Although medetomidine and ketamine hydrochloride can be administered concomitantly, Domitor may only be combined with either Vetalar or Ketaset and administered in the same syringe. To minimise the possibility of cross contamination, the vials of each product should have separate needles inserted for withdrawal. Domitor should be administered at a rate of 80 mcg/kg (0.08 ml/kg) with a concomitant dose of 2.5 - 7.5 mg/kg (0.025 - 0.075ml/kg) of Vetalar or Ketaset (ketamine). Atropine is not normally necessary when using a medetomidine/ketamine combination.

Feline doses (ml) for sedation with Domitor and butorphanol IM or SC:
	Domitor 1mg/ml	butorphanol 10mg/ml
kg	50 mcg/kg	0.4 mg/kg
1	0.05	0.04
1.5	0.08	0.06
2	0.10	0.08
2.5	0.13	0.10
3	0.15	0.12
3.5	0.18	0.14
4	0.20	0.16
4.5	0.23	0.18
5	0.25	0.20

Using this regime the average onset of anaesthesia is 3 - 4 minutes and surgical anaesthesia can be expected to last between 30 and 50 minutes. If required, anaesthesia may be prolonged with halothane and oxygen with or without nitrous oxide.

Food should be withheld for 12 hours prior to anaesthesia.

Domitor, butorphanol and ketamine for feline anaesthesia

a) IM

Dosage: Domitor 80 mcg/kg (0.08ml/kg), butorphanol 0.4mg/kg (0.04ml/kg of 10mg/ml solution) and ketamine 5mg/kg (0.05ml/kg of 100mg/ml solution) should be given in a single syringe

Cats become recumbent in 2-3 minutes following injection. Loss of the pedal reflex occurs 3 minutes post injection.

Reversal with Antisedan 200 mcg/kg ( 0.04 ml/kg) by IM injection results in return of the pedal reflex 2 minutes later, sternal recumbency 6 minutes later and standing 31 minutes later.

Feline doses (ml) for IM Domitor/butorphanol/ketamine anaesthesia:
	Domitor 1mg/ml	butorphanol 10mg/ml	ketamine 100 mg/ml
kg	80 mcg/kg	0.4 mg/kg	5mg/kg
1.5	0.12	0.06	0.08
2	0.16	0.08	0.10
2.5	0.20	0.10	0.13
3	0.24	0.12	0.15
3.5	0.28	0.14	0.18
4	0.32	0.16	0.20
4.5	0.36	0.18	0.23
5	0.40	0.20	0.25

Feline doses (ml) for IV Domitor/butorphanol/ketamine anaesthesia:
	Domitor 1mg/ml	butorphanol 10mg/ml	ketamine 100 mg/ml	ketamine 100 mg/ml
kg	40 mcg/kg	0.1 mg/kg	Minimum 1.25 mg/kg	Maximum 2.5 mg/kg
1.5	0.06	0.02	0.02	0.04
2	0.08	0.02	0.03	0.05
2.5	0.10	0.03	0.03	0.06
3	0.12	0.03	0.04	0.08
3.5	0.14	0.04	0.04	0.09
4	0.16	0.04	0.05	0.10
4.5	0.18	0.05	0.06	0.11
5	0.20	0.05	0.06	0.13

Approximate time scales in IV Domitor / butorphanol / ketamine anaesthesia:
Ketamine dose	1.25 mg/kg	2.5 mg/kg
Time to recumbency	32 secs	22 secs
Time to loss of pedal reflex	62 secs	39 secs
Time to return of pedal reflex	26 mins	28 mins
Time to sternal recumbency	54 mins	62 mins
Time to standing	74 mins	83 mins

b) IV

Dosage: Domitor 40 mcg/kg (0.04 ml/kg), butorphanol 0.1 mg/kg (e.g. 0.01ml/kg of 10mg/ml solution) and ketamine (depending on depth of anaesthesia required) from 1.25 to 2.5 mg/kg (e.g. 0.0125 - 0.025 ml/kg of 100mg/ml solution).

Reversal with Antisedan 100 mcg/kg ( 0.02 ml/kg) by IM injection results in return of the pedal reflex 4 minutes later, sternal recumbency 7 minutes later and standing 18 minutes later.

Domitor followed by alphaxalone/alphadolone for feline general anaesthesia

Dosage: Administer Domitor 80 mcg/kg (0.08ml/kg) by IM or SC injection.

15 - 60 minutes later administer 2.5 - 5.0 mg/kg alphaxalone/alphadolone ( e.g. 0.208 - 0.416 ml/kg of a 12mg/ml solution) IV.

Anaesthesia may be maintained by further IV injections of alphaxalone/alphadolone 1.0 - 2.0 mg/kg (e.g. 0.083 - 0.167 ml/kg of a 12 mg/ml solution), or by administration of halothane in oxygen.

Feline doses (ml) for Domitor( IM or SC) plus alphaxalone/alphadolone (IV) anaesthesia:
	Domitor 1mg/ml	alphaxalone 9mg/ml + alphadolone 3 mg/ml	alphaxalone 9mg/ml + alphadolone 3 mg/ml
kg	80 mcg/kg	minimum dose 2.5 mg/kg	maximum dose 5 mg/kg
1	0.08	0.21	0.42
1.5	0.12	0.31	0.63
2	0.16	0.42	0.83
2.5	0.20	0.52	1.04
3	0.24	0.63	1.25
3.5	0.28	0.73	1.46
4	0.32	0.83	1.67
4.5	0.36	0.94	1.88
5	0.40	1.04	2.08

Antisedan administered in the post-operative phase will hasten the recovery from anaesthesia. Half the volume of Antisedan to that of the previously administered Domitor (medetomidine) should be given by the IM route.

Contra-indications, warnings, etc

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

Contra-indications: The use of Domitor in pregnancy has not been monitored in sufficient animals and is, therefore, not recommended. Domitor should not be used in conjunction with sympathomimetic amines.

Warnings: Care should be taken with the use of Domitor in animals with cardiovascular disease or in poor general health. The concomitant use of other CNS depressants should be expected to potentiate the depressant effects of either product, and appropriate dose adjustment should be made.

Side-effects: Due to the mode of action of Domitor, heart rate and body temperature decrease. Treated animals should be kept warm in an even temperature for 12 hours during the procedure and after sedation. Blood pressure will initially increase and then return to normal or slightly below. Some dogs and many cats will vomit (particularly if recently fed) 5--10 minutes post-injection. Some cats may also vomit at recovery. Occasionally muscle twitching has been observed. Diuresis may occur during recovery.

Overdosage: In cases of overdosage, or should the effects of Domitor become life-threatening, the appropriate dose of Antisedan is recommended provided that reversal of sedation and analgesia is not dangerous to the patient (e.g. Antisedan does not reverse the effects of ketamine). In cases where it is imperative to reverse bradycardia but maintain sedation, atropine may be used.

PREMEDICATION

Domitor has marked anaesthetic-sparing effects. It is essential to appropriately reduce the dose of anaesthetic induction and maintenance agents in animals that have been given Domitor.

Domitor with ketamine in cats: Domitor and ketamine are metabolised in the liver and excreted mainly via the kidneys, thus any pre-existing hepatic or renal pathology must be carefully evaluated before considering this method of anaesthesia. Vomiting prior to onset of anaesthesia occurs in approximately 10% of cases. Laryngeal and pharyngeal reflexes are retained during anaesthesia. The combination has been reported to elicit a pain response in some cats when administered IM. Heart rates will generally fall to approximately 50% of pre-anaesthetic levels and in some cats very slow respiratory rates are observed (4-6 breaths per minute). Where procedures are prolonged it may be helpful to apply an eye preparation at regular intervals to lubricate the cornea. During and after anaesthesia, treated animals should be kept in a warm and even temperature.

Domitor as a premedicant before thiopentone in dogs, anaesthesia being maintained with halothane (with or without nitrous oxide):

This regime should not be used in animals with cardiovascular or respiratory disease. Domitor and thiopentone are metabolised in the liver and excreted via the kidneys; any pre-existing hepatic or renal pathology must be carefully evaluated before considering this method of anaesthesia.

Because Domitor has marked anaesthetic-sparing effects, it should be ensured that the dose of thiopentone and halothane is reduced accordingly and should be administered with care to minimise the possibility of inadvertent overdosage.

Respiratory rates may fall by up to 30% of pre-dose values following administration of Domitor. Heart rates will fall following the administration of Domitor and they will not return to presedation levels following induction. Occasionally there will be a transient rise in heart rate associated with induction followed by bradycardia.

During and after anaesthesia, treated animals should be kept in a warm and even temperature.

Domitor as a premedicant before propofol in dogs. This regime should not be used in animals with cardiovascular or respiratory disease. Domitor and propofol are metabolised in the liver and excreted via the kidneys; any pre-existing hepatic or renal pathology must be carefully evaluated before considering this method of anaesthesia.

Domitor has marked anaesthetic sparing effects. Therefore, it should be ensured that the dose of propofol is reduced accordingly and should be administered with care to minimise the possibility of inadvertent overdosage.

Transient apnoea and movement of the forelegs may occur during induction of anaesthesia and in some cases at higher dosages a decline in arterial oxygen tensions.

When using the regime dogs should be intubated and oxygen administered during anaesthesia. During and after anaesthesia, treated animals should be kept in a warm and even temperature.

OPERATOR WARNING

Because of its potent pharmacological effects skin contact with Domitor should be avoided and impervious gloves worn while administering the solution. Care should be taken to avoid accidental self injection with this potent drug and with combinations. If accidental self injection occurs seek immediate medical attention showing a copy of the product literature(s). Do not drive. The patient should not be left unattended. In case of accidental spillage onto the skin or into eyes, wash the affected area immediately with clean running water. Seek medical attention if irritation persists. In case of accidental ingestion, seek medical advice immediately.

Pharmaceutical precautions

Do not store above 25°C. Do not freeze.

Protect from light.

Discard any contents remaining 28 days after the first dose is withdrawn.

Domitor must not be mixed with other products with the exceptions of Vetalar and Ketaset injections and butorphanol solution.

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

Keep out of the reach of children.

For animal treatment only.

Legal category

POM-V

Packaging Quantities

10 ml vials.

Further information

Cats

When cats have been anaesthetised with Domitor (medetomidine) and ketamine, with or without butorphanol; or Domitor and alphaxalone/alphadolone, to speed recovery from anaesthesia, Antisedan 5 mg/ml solution may be used to reverse the effects of Domitor and so speed recovery from anaesthesia. In the cat half the volume of Antisedan to that of the previously administered Domitor (medetomidine) should be given. This dose of atipamezole in mcg/kg should not exceed four times that of the previously administered medetomidine.

Dogs

In dogs when Domitor has been used, with or without butorphanol, as a premedicant to thiopentone, halothane anaesthesia, or as a premedicant to propofol anaesthesia , Antisedan may be administered in the post-operative phase to reverse the effects of Domitor and hasten recovery. The optimal dose of Antisedan in mcg/kg is 5 times that of the previous medetomidine dose. Thus an equal volume of Antisedan to that of the previously administered medetomidine should be given. Antisedan in the post-operative phase rapidly causes arousal to full awareness and thus radically reduces the period of possible cardiovascular depression and hypothermia.

Domitor has been used for pre-medication in conjunction with other anaesthetic agents in cats and dogs. Domitor may be used in conjunction with local anaesthetics.

Marketing authorisation number

Vm 03649/4001.

Developed and Manufactured by

Orion Corporation, Animal Health Division, Finland.