POM-V Prescription Required Companion Animal

Sympagesic 500 mg/ml + 4 mg/ml Solution for Injection for Horses, Cattle, Pigs and Dogs

Active ingredients: Hyoscine Butylbromide, Metamizole sodium monohydrate

Form

Injection

Species

Cattle Dogs Horses Pigs

Manufacturer

Dechra Regulatory B.V.

VMD MA No.

50406/4008

What it's used for

Horses, cattle, pigs, dogs: treatment of smooth muscle spasms and pain associated with underlying disorders of the gastro-intestinal tract, urogenital syst...

Full indications, dosage and side effects ↓

View official SPC (PDF)

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Prescription required

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Clinical information

Sympagesic 500 mg/ml + 4 mg/ml Solution for Injection for Horses, Cattle, Pigs and Dogs — SPC Details

Source: VMD Summary of Product Characteristics (SPC). Last updated 26 Mar 2026.

Horses, cattle, pigs, dogs: treatment of smooth muscle spasms and pain associated
with underlying disorders of the gastro-intestinal tract, urogenital system and bile
excretory organs.
Horses only: Spasmodic colics.
Cattle, pigs, dogs: Supportive therapy for acute diarrhoea and gastroenteritis.

Horse: slow intravenous use
Pig: slow intravenous use or intramuscular use
single injection of 20 - 25 mg metamizole sodium monohydrate/kg body weight and
0.16 - 0.2 mg hyoscine butylbromide/kg body weight i.e. once 4 - 5 ml per 100 kg.
For pigs, maximum injection volume is 5 mL per injection site.
Cattle: slow intravenous use or intramuscular use
Up to twice daily for three days, 20 - 25 mg metamizole sodium monohydrate/kg
body weight and 0.16 - 0.2 mg hyoscine butylbromide/kg body weight i.e. 4 - 5 ml per
100 kg twice daily up to three days.
Dog: intravenous (slow) or intramuscular use,
single injection of 50 mg metamizole sodium monohydrate/kg body weight and 0.4
mg hyoscine butylbromide/kg body weight i.e. once 0.5 ml per 5 kg. Treatment can
be repeated after 24 hours if necessary.
The stopper must not be punctured more than 25 times.

Do not use in case of hypersensitivity to the active substances or to any of the
excipients.

Unlimited Renewal: August 2023
AN: 01489/2023
Do not use in cases of:
- gastro-intestinal ulceration
- chronic gastro-intestinal disorders
- mechanic obstruction in the gastro-intestinal system
- paralytic ileus
- disorders of the haematopoietic system
- coagulopathies
- renal insufficiency
- tachyarrhythmia
- glaucoma
- prostate adenoma.

In very rare cases, anaphylactic reactions may occur and should be treated
symptomatically.
In very rare cases, cardiovascular shock may occur if the intravenous injection is
administered too fast.
In horses, mild tachycardia may be observed occasionally due to the
parasympatholytic activity of hyoscine butylbromide.
In dogs painful reactions at the injection site can occur immediately after injection,
which abate rapidly and have no negative impact on the expected therapeutic
benefit.
The frequency of adverse reactions is defined using the following convention:
- very common (more than 1 in 10 animals treated displaying adverse reaction(s))
- common (more than 1 but less than 10 animals in 100 animals treated)
- uncommon (more than 1 but less than 10 animals in 1,000 animals treated)
- rare (more than 1 but less than 10 animals in 10,000 animals treated)

Unlimited Renewal: August 2023
AN: 01489/2023
- very rare (less than 1 animal in 10,000 animals treated, including isolated reports).

None.

Special precautions for use in animals
Due to the risk of anaphylactic shock, metamizole-containing solutions should be
administered slowly when given intravenously.
Special precautions to be taken by the person administering the veterinary medicinal
product to animals
In a very small number of people, metamizole can cause reversible, but potentially
serious agranulocytosis and other reactions such as skin allergy. Take care to avoid
self-injection.
In case of accidental self-injection, seek medical advice immediately and show the
package leaflet or the label to the physician.
Avoid skin and eye contact. People with known hypersensitivity to metamizole or
hyoscine butylbromide should avoid contact with the veterinary medicinal product.
Avoid use of the product if you are known to be sensitive to pyrazolones, or are
sensitive to acetylsalicylic acid.
Wash splashes from skin and eyes immediately.

The effects of metamizole and/or hyoscine butylbromide may be potentiated by
concurrent use of other anticholinergic or analgesic substances.
Concomitant use of inducers of hepatic microsomal enzymes (e.g. barbiturates,
phenylbutazone) reduces the half-life period and hence the duration of action of
metamizole. Simultaneous administration of neuroleptics, especially phenothiazine
derivatives, may lead to severe hypothermia. Furthermore the risk of gastro-intestinal
bleeding is increased upon concurrent use of glucocorticoids. The diuretic effect of
furosemide is attenuated.
Co-administration of other weak analgesics increases the effects and side-effects of
metamizole.
The anticholinergic action of quinidine and antihistaminics as well as the tachycardic
effects of β sympathomimetics may be enhanced by this veterinary medicinal
product.

After first opening the immediate packaging do not store above 25°C.

For the full list of excipients, see section

This information is sourced from the official Summary of Product Characteristics (SPC) published by the Veterinary Medicines Directorate (VMD). It is provided for informational purposes only and does not replace professional veterinary advice. Always consult your vet before administering any medication.