POM-V Prescription Required Companion Animal

ProZinc 40 IU/ml Suspension for Injection for Cats and Dogs

Active ingredient: Insulin

Form

Injection

Species

Cats Dogs

Manufacturer

Boehringer Ingelheim Vetmedica Gmbh

VMD MA No.

EU/2/13/152/001-002

What it's used for

of diabetes mellitus (insulin deficiency) in dogs and cats, where the required blood levels are achieved by using an individually adjusted dose of the vete...

Full indications, dosage and side effects ↓

View official SPC (PDF)

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2

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Prescription required

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Clinical information

ProZinc 40 IU/ml Suspension for Injection for Cats and Dogs — SPC Details

Source: VMD Summary of Product Characteristics (SPC). Last updated 27 Mar 2026.

of diabetes mellitus (insulin deficiency) in dogs and cats, where the required blood
levels are achieved by using an individually adjusted dose of the veterinary medicinal
product.

The veterinary medicinal should be administered once or twice daily, as appropriate,
by subcutaneous injection. Alternate the injection site daily. Before first use shake the
vial thoroughly until a homogeneous, uniformly milky suspension is obtained. Foam
on the surface of the suspension formed during shaking should be allowed to
disperse before the veterinary medicinal product is used and, before each
subsequent use, the veterinary medicinal product should be gently mixed to maintain
a homogeneous, uniformly milky suspension before use. Agglomerates can form in
insulin suspensions: do not use the veterinary medicinal product if visible
agglomerates persist after shaking thoroughly.
Vial: Before each use, invert the vial a few times before use until a homogenous
suspension is obtained. A 40 IU/ml insulin syringe should be used.
Cartridge: Before each use, invert the vial a few times before use until a homogenous
suspension is obtained. The glass cartridge is designed to be used with the injector
VetPen 8 or VetPen 16.
VetPen is accompanied by a package leaflet with detailed instruction for use to be
followed. The injection procedure when using VetPen is as follows:
1. Peel the protective film from a new pen needle. Screw the pen needle straight
onto the cartridge holder. Remove the outer protective needle cap from the
pen needle.
Replace the pen cap onto the insulin pen. Turn the pen up and down at least
10 times.
2. It is important to remove the air from the cartridge (prime the pen) before
use to avoid injection of air and ensure proper dosing. Dial 1 unit on the
dose selector. Remove the pen cap and the needle cap.
Position the pen carefully with the needle pointing vertically upwards. Tap the
cartridge gently with your finger a few times to push any air bubbles to the top
of the cartridge. Push and hold the release button towards the needle until the
arrow on the pen body points to the start line (▬) on the dose selector.
A small amount of insulin may appear at the needle tip before the pen is fully
primed. Repeat steps 1 and 2 until insulin drips actively or squirts out of the
needle tip. Confirm that the pen is fully primed by ensuring that the air bubble
is no longer visible in the cartridge window during inversion. The insulin pen is
now primed and ready for use.
3. Make sure the arrow (►) on the pen body points to the start line (▬) on the
dose selector. If it does not, please refer to ‘Priming Advice’ on the leaflet
supplied with the VetPen.
4. Dial up the number of units required per your veterinary surgeon’s direction.
Never attempt to forcefully dial back the dose selector, as doing so may
damage the insulin pen and result in inaccurate dosing. If at any time
you select too high a dose, we recommend that the incorrect dose is
fully expelled into a safe place and the required dose is redialed. Make
sure before injecting that the arrow (►) points towards the correct
number of units on the dose selector.
5. The injection should be performed subcutaneously, 2 to 5 cm (¾ to 2 in) from
the dorsal midline, varying from behind the scapulae (shoulder) to the mid-
lumbar region (mid-back) and alternating sides. Insert the needle using the
injection technique recommended by your veterinary surgeon then push the
release button towards the pen needle and hold it in place until the start line
on the dose selector returns to the arrow on the pen body (►▬).
Releasing the button prematurely will result in incomplete delivery of the dose.
After the start line returns to the arrow, wait for a minimum of 5 seconds
before removing the needle from the skin.
If the needle is removed or dislodged from the skin too early, you may observe small
drops of insulin leaking from the needle, which can result in incomplete dosing. If this
occurs, do not attempt to re-dose. Wait and give your pet its usual dose at the next
injection.
If the dose selector stops before the start line on the dose selector (▬) returns to the
arrow on the pen body (►), this indicates that your pet has not received a full dose. If
only a partial dose is administered, do not attempt to re-dose. Wait and give your pet
its usual dose at the next injection.
When changing between dosing devices (syringes or VetPen), owners should be
advised to monitor their animal closely to detect any changes in behavior or clinical
condition. A dose adjustment may be required.
A once daily injection is sufficient to reduce the blood glucose concentration in most
diabetic dogs.
However, the duration of action may vary, making it necessary to administer the
insulin dose twice daily to some diabetic dogs.
In diabetic cats, it is necessary to administer the veterinary medicinal product twice
daily.
The dose depends on the degree of deficit in the animal's own insulin production and
is therefore different in each case.
Stabilisation phase
Dog: Insulin therapy is initiated with the starting dose of bodyweight
once daily, rounded down to the lowest entire number of units.
Subsequent adjustment to establish the maintenance dose should be made by
increasing or decreasing the daily dose by approximately 10% according to the
evolution of the diabetes clinical signs and to the results of serial blood glucose
measurement. Alterations in dose should not normally be made more frequently than
every 3 days.
The duration of insulin action as determined by blood glucose curve, may require
treatment to be administered twice daily. In such cases, the dose per injection must
be decreased by 25 % so that the total daily dose is less than doubled. For example
for a 10 kg dog receiving 5 IU once daily, the new dose (rounded down to the nearest
whole unit) would be 3 IU per injection initially. The new doses should be
administered at 12-hour intervals. Further dose adjustments should be made
progressively as previously explained. Following switching to twice daily dosing, it is
recommended that the clinical signs and blood glucose response be monitored
closely.
To achieve a balance between the generation of glucose and the effect of the
veterinary medicinal product, feeding should be synchronised with the treatment and
the daily ration divided into two meals. The composition and quantity of the daily food
intake should be constant. In dogs treated once daily, the second meal is usually fed
at the time of peak insulin effect. In dogs treated twice daily, feeding coincides with
insulin administration. Each meal should be fed at the same time each day.
Cat: The initial dose is 1 IU or 2 IU per injection based on the baseline blood glucose
concentration, as presented in the following table. Cats require twice daily
administration.
Cat blood glucose concentrationStarting dose per cat< 20 mmol/l or < 3.6 g/l (< 360 mg/dl)1 IU twice daily 20 mmol/l or  3.6 g/l ( 360 mg/dl)2 IU twice daily
The starting dose should not exceed 2 IU per injection.
The composition and quantity of the daily food intake should be constant.
Subsequent adjustment to establish the maintenance dose should be made by
increasing or decreasing the daily dose according to the results of serial blood
glucose measurement. Alterations in dose should not normally be made more
frequently than every week. Increments of 1 IU per injection are recommended. Due
to the day-to-day variation in the blood glucose response, and the variations in insulin
responsiveness that are seen with time, larger or more frequent increases in dose
are not recommended.
Maintenance phase in dogs and cats
Once the maintenance dose has been reached and the animal is stabilised, a long
term management program needs to be established. The aim should be to manage
the animal in such a way as to minimise the variations in its insulin requirement. This
includes clinical monitoring to detect under or over dosage of insulin and adjustment
of dose if required. Careful stabilisation and monitoring will help to limit the chronic
problems associated with diabetes, including cataracts (dogs), fatty liver (dogs and
cats), etc.
Follow up examinations should be performed every 2-4 months (or more often if there
are problems) to monitor the animal’s health, the owners records and biochemical
parameters (like blood glucose and/or fructosamine concentration). Adjustments to
the insulin dose should be made based on interpretation of the clinical signs
supported by the laboratory results.
Somogyi overswing, also called rebound hyperglycaemia, is a response to an
overdose of insulin insufficient to cause, potentially fatal, hypoglycaemia. As
hypoglycaemia begins to develop, a hormonal response is triggered which results in
the release of glucose from hepatic glycogen stores. This results in rebound
hyperglycaemia which may also manifest as glycosuria for part of the 24-hour cycle.
There is a danger that the Somogyi overswing is interpreted as a requirement for
increase in the insulin dose rather than a decrease. This can be avoided by basing
decisions on serial blood glucose measurements rather than single point
measurements.
The ability of pet owners to recognise the signs of hypo- or hyperglycaemia and
respond appropriately is very important.

Do not administer by the intravenous route.
The veterinary medicinal product is a medium duration insulin and is not intended for
the treatment of animals with severe acute diabetes presenting in a ketoacidotic
state.
Do not use in cases of hypoglycaemia.
Do not use in cases of hypersensitivity to the active substance or to any of the
excipients.

Dogs and cats:
Rare
(1 to 10 animals / 10,000 animals treated):
Hypoglycaemia
Injection site reaction *
Very rare
(<1 animal / 10,000 animals treated,
including isolated reports):
Hypersensitivity reaction
*The reaction is usually mild and reversible. Local injection site reactions are reported
very rarely in cats.
Reporting adverse events is important. It allows continuous safety monitoring of a
veterinary medicinal product. Reports should be sent, preferably via a veterinarian, to
either the marketing authorisation holder or its local representative or the national
competent authority via the national reporting system. See the package leaflet for
respective contact details.

In the cat, diabetic remission is possible.

Special precautions for safe use in the target species:
Before the veterinary medicinal product is administered owners should be instructed
to have a box of powdered glucose at home. Signs of hunger, increasing anxiety,
unstable locomotion, muscle twitching, stumbling or sinking in the rear legs and
disorientation indicate progression of hypoglycaemia and requires immediate
administration of glucose solution and food to restore blood glucose levels.
Polyuria, polydipsia and polyphagia in combination in chronic cases with weight loss,
general bad condition, loss of hair or abnormal furry coat and lethargy are the most
common clinical symptoms of hyperglycaemia and require administration of insulin to
restore blood glucose levels to the normal range.
The use of progestagens (oestrus inhibitors) in patients suffering from diabetes
mellitus should be avoided.
Stress and irregular extra exercise must be avoided. Care must be taken with the use
of corticosteroids. Ovariohysterectomy may have to be considered.
It is important to establish a strict feeding schedule in consultation with the owner
which will include a minimum of fluctuations and changes.
Administration of the veterinary medicinal product must be carried out by an adult
responsible for the welfare of the animal.
The veterinary medicinal product must be administered with specific U-40 sterile
single-use syringes (vial) or with VetPen (cartridge).
Special precautions to be taken by the person administering the veterinary medicinal
product to animals:
Accidental self-injection can provoke clinical signs of hypoglycaemia and there is a
low possibility of an allergic reaction. Do not use in cases of hypersensitivity to the
active substance or to any of the excipients.
In case of accidental self-injection seek medical advice immediately and show the
package leaflet or the label to the physician.
In the unlikely event of accidental eye and skin contact, wash the area with clean,
running water.
Special precautions for the protection of the environment:
Not applicable.

Changes in insulin requirements may result from administration of substances which
alter glucose tolerance, such as corticosteroids, thiazide diuretics, progestogens,
amitraz and alpha-2 agonists, such as medetomidine, dexmedetomidine, xylazine.
Monitoring of glucose concentrations should be used to adjust the dose accordingly.
Similarly, changes in diet or exercise may alter insulin requirements.

Before first use: Store upright in a refrigerator (2 °C – 8 °C).
After first opening: Store below 25 °C. Store the broached vial upright.
Do not freeze.
Keep the vial/cartridge in the outer carton.
Protect from light.

Not applicable.

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.