In the past, injectable epinephrine was used in the emergency room as a treatment for acute asthma attacks or exacerbations that were not responding to standard treatments. Today, there are many new quick relief and controller medicines available to manage asthma symptoms.
In situations where typical asthma treatments are not working to control symptoms, epinephrine may help patients with severe asthma exacerbations. This would be a unique situation. This would typically be done in the emergency room while the patient is monitored.
If no other treatments are working to control asthma symptoms and an Epi-Pen is available, it could be administered. 9-1-1 should be called to activate Emergency medical services. The patient will need to be evaluated and managed in an emergency room.
Finally, there are some patients who have a history of anaphylaxis (e.g. due to a food, venom, or medication) and asthma. It would be fine for these patients to use epinephrine first and then appropriate asthma medications if the patient is not sure if their symptoms are due to an anaphylactic reaction, asthma, or both. Again, the patient would need to be evaluated in the emergency room after these treatments.