Epinephrine is a stimulant drug that can relax muscles and soothe allergic reactions. If a person uses an inhaler to deliver the medicine, then the drug goes directly into the lungs. An epinephrine inhaler is often a prescribed treatment for a person who suffers from asthma or other breathing disorders.
The mode of action of epinephrine is to excite specific cell receptors. These receptors are the alpha and beta receptors in the central nervous system. The result of the stimulation is that smooth muscle, present in the surface of the lungs, relaxes. This drug also acts upon the immune system to reduce the sensitivity that causes some of the symptoms of asthma. It does this by counteracting the biological effects of a molecule called histamine, which raises the intensity of the immune reaction.
Asthma attacks cause the smooth muscle inside the lungs to contract. This contraction narrows the airways and makes it hard for the person with asthma to breathe, so he or she has to get air into and out of the lungs through wheezing. An epinephrine inhaler delivers a dose of medication into the lungs and the patient can then breathe more easily. As well as asthma, other conditions that affect the ability to breathe may also be treatable by an epinephrine inhaler, such as emphysema.
The inhaler is the container and the delivery system for the drug. The patient places the contents of a vial of medicine into the inhaler. When he or she presses the vial into the inhaler, it is released in a breathable mist. A typical dose of the medicine is one to two puffs from the inhaler, repeated once if necessary. Epinephrine can have detrimental effects to health, so the person should not inhale more medicine than is detailed on the product instructions.
Potential side effects of using an epinephrine inhaler are insomnia, excessive nervousness or muscle twitches. The drug can also cause headaches, nausea, a lack of appetite or even rapid heartbeats. Severe allergic reactions can also occur that involve facial swelling, hives or other symptoms that may be dangerous.
In some countries, epinephrine inhalers are readily available without prescription. Other countries regard these specific inhalers as illegal because the inhalers use an outdated form of aerosolization called chlorofluorocarbons (CFCs) that pose a potential risk to the ozone layer. As well as the common inhaled form, epinephrine is available as injections or in some nasal liquids. These forms, however, are not considered suitable for asthma treatment, but rather for conditions such as allergies.