Torphasol 10mg/ml solution for injection for horses 20ml

Torphasol 10mg/ml solution for injection for horses 20ml.

Target species
Horses

Indications for use, specifying the target species
For short term relief of pain associated with colic of gastrointestinal tract origin.
For sedation in combination with certain a2-adrenoceptor agonists.

Contraindications
Butorphanol – as a sole agent and in any combination:
Do not use in horses with a history of liver or kidney disease.
Do not use in case of known hypersensitivity to the active substance or to any of the
excipients.
Do not use in cases of cerebral injury or organic brain lesions (e.g. lesions
following cranial trauma) and in animals with obstructive respiratory diseases,
heart dysfunction or spastic convulsions.

Butorphanol / detomidine hydrochloride combination:
The combination should not be used in pregnant animals.
Do not use the combination in horses with a pre-existing cardiac dysrhythmia or
bradycardia.
Do not use in horses with emphysema due to a possible depressive effect in the
respiratory system.
Butorphanol / romifidine combination:
Do not use during the last month of pregnancy
Butorphanol / xylazine combination:
The combination should not be used in pregnant animals.
Any reduction in gastrointestinal motility caused by butorphanol (see section 4.6)
may be enhanced by the concomitant use of a2-adrenoceptor agonists.
Consequently, such combinations should not be used in cases of colic associated
with impaction.

Special warnings for each target species
None.

Special precautions for use

Special precautions for use in animals
Safety and efficacy of butorphanol in foals have not been established. In foals use
the product only according to the benefit/risk assessment by the responsible
veterinarian.
Due to its antitussive properties, butorphanol may lead to an accumulation of mucous
in the respiratory tract. Therefore, in animals with respiratory diseases associated
with increased mucous production or in animals that are being treated with
expectorants, butorphanol should only be used on the basis of a risk-benefit analysis
by the responsible veterinarian.
The use of the product at the recommended dose may lead to transient ataxia and/or
excitement. Therefore, to prevent injuries in patient and people, the location for the
treatment should be chosen carefully.
Butorphanol / detomidine hydrochloride combination:
Routine cardiac auscultation should be performed prior to use in combination with
detomidine.

Special precautions to be taken by the person administering the veterinary
medicinal product to animals
Direct contact with skin or eye of the user should be avoided since the product might
induce irritation and sensitization. Accidental spillage on the skin should be washed
immediately with soap and water. When the product comes into contact with the
eyes, rinse immediately with plenty of water.
Care should be taken when handling the product to avoid self-injection. In case of
accidental self-injection, seek medical advice immediately and show the package
insert or the label to the physician, and DO NOT DRIVE, since drowsiness, nausea and dizziness may occur. Effects can be reversed by the administration of an opioid
antagonist.

Adverse reactions
Butorphanol may cause the following side-effects:
- Excitatory locomotor effects (pacing)
- Mild sedation (may occur following the administration of butorphanol as a sole
agent)
- Ataxia
- Reduction in gastrointestinal motility
- Depression of cardiovascular system

Use during pregnancy, lactation or lay
The safety of this product has not been investigated in the target species during
pregnancy and lactation. The use of butorphanol during pregnancy and lactation is
not recommended.

Interaction with other medicinal products and other forms of interaction
Butorphanol may be used in combination with other sedatives such as a2-
adrenoceptor agonists (e.g. romifidine, detomidine, xylazine) where synergistic
effects can be expected. Therefore, an appropriate reduction in dose is necessary
when used concomitantly with such agents.
Because of its antagonist properties at the opiate mu receptor, butorphanol may
inhibit the analgesic effect in animals, which have already received pure opioid mu
agonists (morphine/oxymorphine).
Because of the antitussive properties of butorphanol, it should not be used in
combination with an expectorant, as this may lead to an accumulation of mucous in
the airways.
The combination of butorphanol and a2-adrenoceptor agonists should be used with
caution in animals with cardiovascular disease. The concurrent use of anticholinergic
drugs, e.g. atropine should be considered.

Amount(s) to be administered and administration route
For intravenous administration only.
For analgesia:
Dose rate: 100 µg butorphanol per kg bodyweight (BW) (equivalent to 1 ml for 100 kg
BW), by intravenous injection. Butorphanol is intended for use where short duration
analgesia is required. The dose may be repeated as required. The need for and
timing of repeat treatment will be based on clinical response. For information on the
onset and duration of analgesia see section 5.1. For cases where longer duration
analgesia is likely to be required, an alternative therapeutic agent should be used.

For sedation in combination with detomidine hydrochloride:
A dose rate of 12 µg detomidine hydrochloride per kg BW should be given
intravenously followed within 5 minutes by a dose rate of 25 µg butorphanol per kg
BW (equivalent to 0.25 ml for 100 kg BW) intravenously.
For sedation in combination with romifidine:
A dose of 40-120 µg romifidine per kg BW followed within 5 minutes by a dose rate of
20 µg butorphanol per kg BW (equivalent to 0.2 ml for 100 kg BW) should be
administered intravenously.
For sedation in combination with xylazine:
A dose rate of 500 µg xylazine per kg BW followed immediately by a dose of 25-50
µg butorphanol per kg BW (equivalent to 0.25-0.5 ml per 100 kg) should be
administered intravenously.

Overdose
The main sign of overdose is respiratory depression which can be reversed with an
opioid antagonist (naloxone). Other possible signs of overdose in the horse include
restlessness/excitability, muscle tremor, ataxia, hypersalivation, decrease of
gastrointestinal motility and seizure.

Withdrawal periods
Meat and offal: zero days.
Milk: zero days.

PHARMACOLOGICAL PROPERTIES
Pharmacotherapeutic group: Synthetic opioid (morphinan derivatives), centrally
acting analgesic.
ATCvet code QN02AF01

Pharmacodynamic properties
Butorphanol tartrate (R(-) enantiomer) is a centrally acting analgesic. Its action is
agonist-antagonist at the opiate receptors in the central nervous system; agonist at
the kappa opioid receptor subtype and antagonist at the mu receptor subtype. The
kappa receptors control analgesia, sedation without depression of cardiopulmonary
system and body temperature, whereas the mu receptors control supraspinal
analgesia, sedation and depression of cardiopulmonary system and body
temperature. The agonist component of butorphanol activity is ten times more potent
than the antagonist component.
Onset and duration of analgesia:
Analgesia generally occurs within 15 minutes following intravenous administration.
After a single intravenous dose in the horse, analgesia usually lasts for 15-90
minutes.

Pharmacokinetic particulars
Following intravenous injection, butorphanol is well distributed in tissue. Butorphanol
is metabolised extensively in the liver and excreted in the urine. In horses,
butorphanol administered by intravenous route has a high clearance (21ml/kg/min)
and a short terminal half-life (44 minutes), indicating that 97% of a dose will be
eliminated after intravenous administration in, on average, less than 5 hours.

PHARMACEUTICAL PARTICULARS
List of excipients
Benzethonium chloride
Citric Acid Monohydrate
Sodium Citrate
Sodium Chloride
Water for injections

Incompatibilities
In the absence of compatibility studies, this veterinary medicinal product must not be
mixed with other veterinary medicinal products.

Shelf-life
Shelf-life of the veterinary medicinal product as packaged for sale: 3 years
Shelf-life after first opening the immediate packaging: 28 days.

Special precautions for storage
Keep the vial in the outer carton in order to protect from light.

Nature and composition of immediate packaging
Cardboard box with 1 clear glass vial (type I) of 20 ml with a grey butyl rubber
stopper and an aluminium cap.

Special precautions for the disposal of unused veterinary medicinal
product or waste materials derived from the use of such products, if
appropriate
Any unused veterinary medicinal product or waste materials derived from such
veterinary medicinal products should be disposed of in accordance with local
requirements.