Prevention and proper hydration is key to avoiding all heat-related illnesses, and the cornerstone of prevention is to allow your body enough time to acclimatize to a new heat challenge. With that said, the drugs listed below can predispose outdoor adventurers to a variety of heat illnesses and heat-related problems. Check to see if your friends, clients, or students are taking any of them before venturing into the outdoors this summer when it's hot outside. (A printed drug guide, app, or website will help you understand the side effects, contraindications, and administration guidelines for most drugs.)  If you find that they are taking a drug that predisposes them to a heat illness:

1. Avoid outdoor trips that will expose them to a significant heat challenge.
2. If you decide to go on the trip in the face of a moderate heat challenge—as many people do—make sure to allow time for them to acclimate to current and new heat challenges, carry enough water to ensure adequate hydration (and to cool them should it become necessary), minimize exercise (especially during the hottest time of day), carry reliable communication, and have an emergency evacuation plan in place.

Anticholinergics
Anticholinergic drugs block the transmission of the neurotransmitter acetylcholine in the central and peripheral nervous system responsible for the autonomic control of the smooth muscles primarily in the gastrointestinal (GI) tract, the genitourinary tract, and the lungs. They are used to treat:

• vertigo and motion sickness
• peptic ulcers, diarrhea, diverticulitis, ulcerative colitis, nausea and vomiting (GI problems)
• cystitis, urethritis, and prostatitis (GU problems)
• asthma, chronic bronchitis, COPD (respiratory problems)
• slow heart rate due to a hypersensitive vagus nerve. 

Anticholinergics inhibit sweating—and therefore cooling—and predispose people to both heat exhaustion and heat stroke.

Antihistamines 
Antihistamines block histamine receptor sites in mast cells and basophils, smooth muscle, the lining of lymph and blood vessels, and histamine-releasing neurons in the brain. There are two subcategories of antihistamines: H1 and H2; both are used to treat allergies. H2 antihistamines, because they bind to histamine receptors in the gut, are also used to treat peptic ulcers and acid reflux and H1 antihistamines, because they cross the blood-brain barrier and bind to histamine receptors in the hypothalamus, may be used to treat insomnia in adults and motion sickness. Similar to anticholinergic drugs, antihistamines inhibit sweating and predispose people to both heat exhaustion and heat stroke.

Opioids
Opioids—including their semi-synthetic and synthetic derivatives—are used to manage both acute and, to a lesser extent, chronic pain; strong opioids are highly addictive. Codeine, a weak opioid, is commonly used in over-the-counter (OTC) pain medications and cough suppressants. Loperamide, an  opioid that cannot cross the blood-brain barrier acts on the large intestine to suppress diarrhea. All opioids decrease blood flow to the skin and predispose people to heat stroke.

Pseudoephedrine
Pseudoephedrine is a stimulant that acts on the smooth muscle lining the blood vessels and bronchi causing them to constrict; it is used to treat sinus and nasal congestion and promote drainage of the sinuses and the Eustachian tubes. Because it's a vasoconstrictor, pseudoephedrine decreases blood flow to the skin and predisposes people to heat exhaustion and heat stroke.

Diuretics
Prescription diuretics are first-line drugs used to treat high blood pressure. Along with caffeine, prescription diuretics promote dehydration via excessive urination and, through that route, predispose people to heat exhaustion, heat stroke, and—because they deplete the body of sodium—hyponatremia. ​

Selective Serotonin Reuptake Inhibitors (SSRIs)
SSRIs are a class of drugs primarily used to treat depression and anxiety disorders but may also be used to treat post traumatic stress disorders (PTSD). The exact therapeutic mechanism is unknown and the side effects of SSRIs may outweigh their benefit. All SSRIs can cause dehydration, which, in turn, can lead to more serious heat illnesses.

Ibuprofen & Naproxen 
Both ibuprofen & naproxen belong to a family of drugs called non-steroidal anti-inflammatory drugs (NSAID) that are commonly carried in first aid kits to treat pain or reduce a fever. While neither drug predisposes people to a heat illness, CAUTION is advised as they can cause kidney damage in the presence of dehydration.

Antipsychotics
Antipsychotics block receptor sites in the brain's dopamine pathways and are used to treat schizophrenia and bipolar disorders, and combined with antidepressants to treat depression in the short term. Unfortunately, they can inhibit the body’s ability to regulate temperature and predispose people to heat stroke.

Beta Blockers
Beta receptors are found in the smooth muscle cells of arteries, bronchi, kidneys, and the heart. When stimulated by epinephrine and other stress hormones, they cause a sympathetic stress response that, among other things, increases heart rate and blood pressure. Beta blockers weaken the stress response and are primarily used to manage abnormal heart rhythms and prevent a second heart attack. (They may also be used to treat high blood pressure but are not as effective as diuretics.) They reduce blood flow to the skin and and predispose people to heat stroke.

Calcium Channel Blockers
Calcium channel blockers disrupt the movement of calcium through cell membranes and are used to treat high blood pressure. They help increase the elasticity of the wall of large blood vessels allowing them to stretch and expand. In this way they also reduce chest pain caused by angina pectoris. They are more effective than beta blockers but have more side effects. Similar to beta blockers, they also reduce blood flow to the skin and predispose people to heat stroke.

Ephedrine, Amphetamines, & Cocaine 
Ephedrine, amphetamines, and cocaine are central nervous system stimulants. Ephedrine is used as a stimulant, appetite suppressant (currently banned in the United States), concentration aid, and decongestant; it works by increasing the activity of norepinephrine. Amphetamines are used to treat attention deficit hyperactivity disorder (ADHD) and narcolepsy. Cocaine is made from the leaves of the coca shrub with no current medicinal use; it is primarily used as a recreational drug...as are many amphetamines. ​Ephedrine, amphetamines, and cocaine increase internal body temperature, constrict blood vessels, and predispose people to heat exhaustion and heat stroke.

Tricyclic Antidepressants
Tricyclic Antidepressants (TCAs), as the name implies, are primarily used in the treatment of mood disorders; they are also used to treat chronic neuropathic pain and as migraine prophylaxis (but will not treat a migraine attack). TCAs also decrease sweating and inhibit the body’s ability to regulate temperature and predispose people to heat exhaustion and heat stroke. ​

ACE Inhibitors
ACE inhibitors are primarily used to treat heart and kidney problems. They block the production of enzymes that cause vasoconstriction and permit blood vessels to relax (dilate) reducing both blood and kidney pressure. ACE inhibitors may cause increased sweating in some patients, which may quickly lead to dehydration in a heat challenge, and by that route predispose people to heat exhaustion and heat stroke.

Looking for a reliable field reference? Consider consider purchasing one of our print or digital handbooks; our digital handbook apps are available in English, Spanish, and Japanese. Updates are free for life. A digital SOAP note app is also available.

You are part of a search and rescue team looking for two lost climbers on Mount Washington. The search is entering its third day when, with the help of rescue dogs, the climbers are both located in a snow cave that was hidden from view by a fresh layer of snow from a storm the previous night. The climbers are both unresponsive with no pulse or respirations. They are huddled together and wearing parkas. One of the climbers, James Standing, has an angulated lower right leg; the other climber, Asa Cochran, appears to be uninjured. The average temperatures on the mountain ranged from a daytime high of 16º F to a nighttime low of -4º F. The day is clear with a light wind, and a helicopter is on standby at the Appalachian Mountain Club lodge on Route 2 at the base of the mountain. You are in communication with the lodge and Incident Command via satellite phone.

What is wrong with James and Asa and what should you do? Click here to find out.

Introduction
Trip medical forms can reduce program liability and help administrators and field staff prevent injuries and illnesses. In most cases, prevention is accomplished through appropriate screening of participants and modifying the structure of a trip by adjusting the trip’s activities and routes to accommodate individual medical conditions or concerns. The type and format of a trip medical form affects the quality of information received and the ability of program administrators and field staff to prevent and treat injuries and illness in the field.

Why require medical forms for trips?

• Accident/illness prevention via screening
• Accident/illness prevention via course design/structure by program administration (preferred and requires time to prepare/adjust)
• Accident/illness prevention via individual & group management by field staff (may be necessary if discovered during the trip). If a physical disability or an ongoing medical problem are discovered during the trip, it may be necessary to assess both the group's and the individual's abilities in light of the newly discovered disability or problem as well as the proposed activity progression and environment before continuing with the trip as planned.​

How is client medical information collected?
Medical information may be collected orally from the client or via a written medical form. Collection is more effective if all involved—client, guide/instructor, healthcare provider, etc.—know why the information is important and how it will be used.
There are two basic types of written medical forms: Those completed by a health care professional (physician, PA, or nurse), and those completed by the client (self-reporting).
Medical forms completed by a health care professional—especially if they are the client's personal physician—tend to be the most accurate. Those completed by professionals with little or no previous knowledge of the client—college or university clinics, for example—can miss some conditions if the providers rely heavily on patient self-reporting.
Self-reporting may be oral or written. Oral self-reporting typically takes place the day of the trip, often as clients are ready to embark on the trip. The accuracy of oral self-reporting is questionable as it's easy for clients to forget something important or simply not mention it for fear they will not be permitted to go on the trip. Clearly written self-reporting forms are better than oral self-reports.
Written forms—regardless of whether completed by a healthcare professional or by the client—tend to be more effective when a combination of check boxes and open-ended questions are used. For example, here's a question with Yes/No checkbox followed by a series of open-ended questions asking for more information:

"Are you taking any prescription medications?" (Yes/No)

"If you answered "yes" to the above question please:

• List the medication, dose, the reason for taking it.
• Are you current with each medication?
• If you plan to carry this medication with you on the trip, are there any storage requirements we need to be aware of?

If client medical information is so important, why don't all outdoor programs collect it?

• Personal health information is protected by the Health Insurance Portability and Accountability Act of 1996 (HIPAA). While there are hundreds of ways that HIPAA rules can be violated, the most common with respect to outdoor programs is an organization's failure to control access to a client's personal health information (PHI) this includes the online transmission of PHI data. While a HIPAA violation is easy to avoid by simply not requesting clients to complete a written medical form, the lack of personal health information may have significant consequences in a remote setting if clients or guides are not prepared to address an emerging medical problem. The Family Educational Rights and Privacy Act of 1974 (FERPA) prohibits student trip leaders—but not professional trip leaders—from receiving medical information of other students. In some cases, a FERPA violation can be avoided if the student contractually waives their FERPA rights for the purpose of attending a student-led outdoor trip.
• Forms completed by a healthcare provider may cost the client additional money. As such, they are typically reserved for longer, more remote trips where the medical form is part of an overall admissions process. Once received, each form is reviewed by a trained person who may contact the individual or their provider for additional information. Outward Bound and NOLS are two organizations that require prospective students to meet with their personal physician and have them complete the organization's medical form as part of their admissions process. Some colleges and universities require trip participants to go to the college or university health system to have a medical form completed.
• Simple checklist forms with a few open-ended questions are easy to complete and, as such, are often used by outfitters on day or weekend trips that will have access to 911 systems. Clients are typically asked to complete them the day of the trip or bring the completed form with them.
• More detailed forms tend to yield more usable information. Usable meaning being able to guide a potential client to the trip that best suits them or adapting an existing trip to meet their medical and/or physical needs. The earlier a medical form is received by an outfitter, the more time they have to respond.

As mentioned earlier, it is extremely important for outdoor programs and outfitters to accurately describe the trip and its associated hazards and to share how a client's Personal Health Information (PHI) will be used. Consider integrating PHI information into the program's release form to obtain permission to treat the client should it become necessary during the trip, permission to allow the program/outfitter to share and transmit PHI information with guides etc. for the protection and safety of the client during the trip, as well as release the organization from any known and unknown hazards.

With the worldwide increase in natural disasters, wilderness medicine graduates are uniquely poised to help their neighbors in the event of a local disaster. Communities in all 50 states have organized Community Emergency Response Teams (CERT). CERT members are volunteers, and teams are structured so that local managers have the flexibility to adapt the program and their training to the specific needs of their community. The concept originated with the Los Angeles City Fire Department in 1985 and went national through the Federal Emergency Management Agency (FEMA) in 1993. Contact your local fire, police, or sheriff department for more information or visit the CERT website.