WS Run Ask-a-Medic
Risk for Hyperthermia
While we are on the topic of medications, I would like to raise attention to the antihistamines, phenothiazines and tricyclic antidepressants. These medications have anticholenergic properties and can be dangerous in the setting of a hot environment. They can increase the risk of hyperthermia. Hyperthermia is a life-threatening emergency.
Simply, an anticholenergic drug blocks the parasympathetic nervous system. The parasympathetic nervous system will increase sweating, salivation, gastric mobility, slow the heart rate, and constrict the pupils and aid in urination. When you block this system to excess, the opposite occurs. If you cannot sweat, then you loose your ability to cool your self.
The most common of these drugs is the antihistamine diphenhydramine, (Benadryl)! I keep Benadryl in my medical aid pack and it can be a life saving drug for a severe allergic reaction. It also can help with motion sickness and nausea. Benadryl is an active ingredient in over the counter sleep aids and cold preparations. Many people treat their own symptoms of allergies with one of these medications. There are also the newer selective preparations like Clariton, Clarinex, Allegra, and Zyrtec.
The well-known phenothiazine is prochlorperazine maleate (Compazine). This medication is given to adults for nausea and vomiting. A similar drug is metoclopramide, (Reglan). Promethazine (Phenergan) is also commonly prescribed for nausea and vomiting. These drugs also have anticholenergic properties and can predispose a person to hyperthermia.
Although the tricyclic antidepressants are an older class of antidepressants, we frequently prescribe them for other mood disorders, chronic pain and as sleep aids. Not only do they cause a dry mouth and decreased gastrointestinal mobility, they increase heat production by decreasing the sweating mechanism!
If any of these medications ring a bell for you, please think twice prior to using them in any arena that places you at risk for hyperthermia. There are alternative solutions for hay fever and allergies. Nausea and vomiting may not be completely diverted in ultra distance running, but eating and hydrating strategies can certainly help reduce the incidence.
I will return on March 18th from a ten-day medical mission to Guatemala. Keep training. Right, left, right, left.
LLee
Simply, an anticholenergic drug blocks the parasympathetic nervous system. The parasympathetic nervous system will increase sweating, salivation, gastric mobility, slow the heart rate, and constrict the pupils and aid in urination. When you block this system to excess, the opposite occurs. If you cannot sweat, then you loose your ability to cool your self.
The most common of these drugs is the antihistamine diphenhydramine, (Benadryl)! I keep Benadryl in my medical aid pack and it can be a life saving drug for a severe allergic reaction. It also can help with motion sickness and nausea. Benadryl is an active ingredient in over the counter sleep aids and cold preparations. Many people treat their own symptoms of allergies with one of these medications. There are also the newer selective preparations like Clariton, Clarinex, Allegra, and Zyrtec.
The well-known phenothiazine is prochlorperazine maleate (Compazine). This medication is given to adults for nausea and vomiting. A similar drug is metoclopramide, (Reglan). Promethazine (Phenergan) is also commonly prescribed for nausea and vomiting. These drugs also have anticholenergic properties and can predispose a person to hyperthermia.
Although the tricyclic antidepressants are an older class of antidepressants, we frequently prescribe them for other mood disorders, chronic pain and as sleep aids. Not only do they cause a dry mouth and decreased gastrointestinal mobility, they increase heat production by decreasing the sweating mechanism!
If any of these medications ring a bell for you, please think twice prior to using them in any arena that places you at risk for hyperthermia. There are alternative solutions for hay fever and allergies. Nausea and vomiting may not be completely diverted in ultra distance running, but eating and hydrating strategies can certainly help reduce the incidence.
I will return on March 18th from a ten-day medical mission to Guatemala. Keep training. Right, left, right, left.
LLee
posted by Linda Lee at
4:22 PM
5 Comments
