The main purpose of this study is to evaluate the safety of nasal glucagon (NG) in participants with a common cold, some of whom will also take a nasal decongestant. The study will investigate how the body processes NG and the effect of NG on the body. The study will last up to 30 days for each participant.

Inclusion Criteria:

• Male or female participant presenting a score of 2 or 3 on nasal congestion and/or nasal discharge associated with at least one other symptom of common cold, as determined by the 8-item Jackson cold scale at screening and prior to dosing of period 1.
• Participant with a body mass index (BMI) greater than or equal to 18.50 and below 30.00 kilogram per square meter (kg/m²).
• Light-, non- or ex-smokers.
• Have no clinically significant diseases captured in the medical history or evidence of clinically significant findings on physical examination and/or clinical laboratory evaluations (hematology, biochemistry, electrocardiogram [ECG] and urinalysis).

Exclusion Criteria:

• Presence of any nose piercings.
• History of significant hypersensitivity to glucagon, oxymetazoline or any related products (including excipients of the formulations) as well as severe hypersensitivity reactions (like angioedema) to any drugs.
• Presence of significant gastrointestinal, liver or kidney disease, or any other conditions known to interfere with the absorption, distribution, metabolism or excretion of drugs or known to potentiate or predispose to undesired effects.
• Presence of significant cardiovascular, pulmonary, hematologic, neurological, psychiatric, endocrine, immunologic or dermatologic disease.
• Presence of severe fever (more than 39.5 degrees Celsius) at screening or prior to dosing of period 1.
• Presence of clinically significant findings on nasal examination or bilateral anterior rhinoscopy, such as structural abnormalities, nasal polyps, marked septal deviation, nasal tumors.
• Presence or history of Type 1 or Type 2 diabetes.
• Presence or history of significant hypoglycemia or hyperglycemia.
• Use of beta-blockers, indomethacin, warfarin or anticholinergic drugs in the previous 28 days before day 1 of the study.
• Fasting blood glucose above 6.1 mmol/L at screening, following a 12-hour fasting period.
• Fasting blood glucose assessed with a glucose meter above 6.1 mmol/L approximately 0.5 hour before each dosing.

All participants enrolled in Period 1.

First dose of study drug (Day 1) until post-study completion (Day 30).