No sign of the anticipated effect.

The investigators will study the effect of microdoses of glucagon at the site of subcutaneous insulin injection. The investigators have unpublished data from anesthetized pigs indicating a major enhancement of insulin absorption.

People with type 1 diabetes will come fasting in the morning to the research facility on two separate days. Both days participants will have a breakfast of their own choice and their regular dose of meal insulin injected. Lyumjev will be used. Frequently collected blood sampled will be analysed for glucose, insulin and glucagon for 3.5 hours. The procedures will be exactly the same both days except that on one of the days they will be randomised to a small dose of glucagon that will be injected at exactly the same site as Lyumjev insulin is injected.

Inclusion Criteria:

1: Type 1 diabetes for at least 1 year. 2. Age 18 - 70 years. 3. Last known HbA1c <86 mmol/mol. 4. Treated with continuous subcutaneous insulin infusion (CSII) by an insulin pump or multiple daily insulin injections (MDII).

Exclusion Criteria:

1. Pregnant women or women trying to conceive.
2. Any chronic disease, including psychiatric illness, judged incompatible with participation in the study.
3. Unfit for participation for any reason judged by the investigators.
4. Known hypersensitivity to glucagon or any of the excipients of the drug formulation.
5. Known phaeochromocytoma. -