Brief Answer:
Watch for allergic reactions.

Detailed Answer:
HI Mr. XXXX,

Both human and Dog's insulin have the same effect on lowering blood sugar levels.

Difference between human and Dog's insulin is the source of insulin.
Human insulin is synthesized by DNA recombinant technology by using yeast (fungus) while dog insulin is derived from animal sources like beef(bovine) or pork (porcine).

In past years Bovine and porcine insulin was used in human safely when human insulin was not available.

Only issue with use of animal insulin is the possibility of allergic reaction.
Allergic reaction may vary from itching and rashes at the site of infection to breathing difficulties, swollen lips and throat, sudden fall in blood pressure.

Another issue may be strength of two insulin preparations (insulin units per ml of preparation) and syringe used to inject. If there is difference in the strength of insulin preparations wrong dose may have been injected.

So you should not worry about use of your dog's insulin only thing is you need to watch for any allergic reaction and symptoms of hypoglycemia (low blood sugar level).
If any allergic reaction started you should consult your doctor.

Hope this may be helpful to you.
I will be happy to answer your further questions.

Regards,
Dr Abhay Mali,
Diabetologist.

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