Although an epi-pen-like device is the correct treatment for anaphylaxis, if the patient's airway is becoming obstructed, and adrenaline is not available (or has already been expended), several puffs an asthma inhaler intended for treating an acute asthma attack, particularly one containing salbutamol, can provide some relief. Ideally, it should be delivered through a spacer. 

In my experience, more people carry asthma inhalers than epi-pens. However, this should only be done when the consequences of doing nothing may include the patient dying, and you should still seek emergency help.

Salbutamol is a bronchodilator, and will dilate the airways in the lungs, but will not help to relieve an upper airway obstruction.