Laryngospasm could be allergic reaction to sting


Dear Doctors: I have a slight allergy to wasp stings. The morning after a sting left me with a swollen lower lip, and I woke with a dry cough. Then my throat closed, and I couldn’t breathe. It lasted for 45 seconds and was terrifying. My sister, an RN, suspects it’s laryngospasm. Can you explain? What do I do if it happens again? I have an EpiPen, but I’ve never used one before.

Dear Reader: To understand laryngospasm, we should start with the larynx. Also known as the voice box, it’s located at the front of the neck, above the windpipe, or trachea. It’s made up of cartilage and ligaments and contains the two bands of smooth muscle tissue that make up the vocal cords, along with a flap of cartilage known as the epiglottis. The larynx performs several important functions. These include creating the vocal sounds we use for speech, directing inhaled air into the trachea and to lungs, directing food into the esophagus and to the stomach, and preventing air and food from entering the wrong pathways. The cough reflex, which protects the airways, is also centered in the larynx.

Laryngospasm refers to the sudden and uncontrolled tightening of the muscles that surround the vocal cords. It’s the body’s attempt to protect the airways from a perceived threat. When laryngospasm occurs, airflow to the lungs is either partially or completely blocked. The individual is unable to breathe or to speak. Although it’s temporary, it is indeed a frightening experience. As happened in your case, the spasm typically passes within a moment or so, and the muscles are released.

Elizabeth Ko, MD and Eve Glazier, MD

The exact cause of laryngospasm is not fully understood, but episodes are usually associated with an existing condition. The most common link is to chronic acid reflux, in which the harsh acids from the stomach back up into the esophagus and irritate the vocal cords. It has also been linked to a history of asthma or chronic obstructive pulmonary disease, stress and anxiety, and it can occur in response to anesthesia during surgery.

Based on the series of events that you have described, including developing a severely swollen lip after being stung, we suspect your bout of laryngospasm was part of an allergic reaction to that sting. Although you characterized your allergy to wasp stings as “slight,” a severely swollen lip is actually a robust response. Using the EpiPen that you have been prescribed to manage your allergy can help, both with the facial swelling and the subsequent laryngospasm. Since it sounds as though you may be unsure of when using the EpiPen is appropriate, we recommend that you make an appointment with the health care provider who prescribed it to you. You can discuss the episode of laryngospasm and review the steps you need to take to manage your wasp and bee sting allergy. It’s possible for subsequent stings to elicit a stronger reaction, and you want to be prepared to make decisions and take action. When it comes to laryngospasm, the good news is that it’s rare. It’s quite possible you may never have one again.

(Send your questions to [email protected], or write: Ask the Doctors, c/o UCLA Health Sciences Media Relations, 10960 Wilshire Blvd., Suite 1955, Los Angeles, CA 90025. Owing to the volume of mail, personal replies cannot be provided.)