BMA Concise Guide to Medicine & Drugs


Brand name GlucaGen

Used in the following combined preparations None


Drug group Drug for diabetes

Overdose danger rating Low

Dependence rating Low

Prescription needed Yes

Available as generic No


Glucagon is a hormone produced by the pancreas. A synthetic injectable form of glucagon is used as an emergency treatment for low blood sugar (hypoglycaemia) in unconscious diabetic patients on insulin. It has the opposite effect on blood sugar to insulin: it raises blood sugar by mobilizing liver stores of glycogen, which is released into the bloodstream as glucose. Glucagon will not work when the liver’s glycogen stores are depleted, for example, in extreme fasting or starvation, in alcohol-induced hypoglycaemia, or if there is impaired adrenal gland function. Although usually administered by medical personnel, glucagon packs may be given to some diabetic patients for emergency use. Glucagon also blocks the activity of smooth muscle in the intestines and so may be used to test bowel motility. It can also stimulate contraction of heart muscle so may be used to treat severe beta-blocker overdoses.


Your drug prescription is tailored for you. Do not alter dosage without checking with your doctor.

How taken/used Injection.

Frequency and timing of doses Hypoglycaemia Single intramuscular or subcutaneous injection. Bowel motility testing Single intravenous injection.

Adult dosage range 1mg.

Onset of effect Within 10 minutes.

Duration of action Up to 40 minutes (intramuscular/subcutaneous injection) or 20 minutes (intravenous injection).

Diet advice If used to treat hypoglycaemia, carbohydrates should be eaten as soon possible after the injection to prevent further hypoglycaemia.

Storage Store at 2–8°C; do not freeze, protect from light, and keep out of the reach of children. The drug should be reconstituted from its powder form just before administration. Packs for personal use in emergencies will last up to 18 months.

Missed dose Not applicable as the drug is for one-off use only.

Stopping the drug Not applicable as the drug is for one-off use only.

Exceeding the dose If the drug is used under medical supervision, overdosage is unlikely. In other situations, exceeding the dose is unlikely to cause major problems but you should consult your doctor promptly.


The adverse effects of glucagon vary according to its use. If used as an emergency treatment for hypoglycaemia in a person with diabetes, the most common adverse effects are nausea and vomiting. It may also cause abdominal pain. If a rash or swelling of the lips or tongue occur, the drug should be stopped and immediate medical help sought. If glucagon is used for diagnostic purposes, adverse effects are rare but may include symptoms of hypoglycaemia (such as faintness, confusion, dizziness, and sweating), low blood pressure, and palpitations. If any of these symptoms occur, you should tell the doctor immediately and the drug should be stopped.


Insulin counteracts the effects of glucagon.

Indomethacin may reduce the effectiveness of glucagon.

Warfarin Glucagon may increase the effects of warfarin.


Be sure to tell your doctor if:

· You have heart problems.

· You have a phaeochromocytoma (a rare tumour of the adrenal gland).

· You have an insulinoma or glucagonoma (rare tumours of the pancreas).

· You are allergic to glucagon or lactose.

· You are taking other medicines.

Pregnancy No evidence of risk.

Breast-feeding No evidence of risk.

Infants and children Reduced dose necessary.

Over 60 Increased likelihood of adverse effects.

Driving and hazardous work If the drug has been used to treat hypoglycaemia, avoid such activities until all signs of hypoglycaemia have disappeared. If the drug has been used diagnostically, avoid such activities until after carbohydrates have been consumed.

Alcohol Avoid until blood sugar levels are normal.


Glucagon is not used long term.