

Summer heat and sun may potentially put some medication users and alcohol and/or drug abusers at increased risk. The following summarizes the Health Alert issued by the Cincinnati Drug and Poison Information Center.
Remember! Do not stop taking any prescribed medication without first talking to your doctor.
The body needs to maintain a relatively consistent temperature to function properly, about 98.6 degrees Fahrenheit. Some medicines can block the body?s natural ability to adjust to changes in temperature. This can result in overheating, which is considered to be a medical emergency.
As the outside temperature increases, the body keeps from overheating by releasing excess heat. The most important ways the body releases heat are by:
These two actions work together-- increasing blood flow to the skin brings heat to the surface of the body where the skin acts like a large radiator. Sweating increases heat loss from the skin through the process of evaporation.
To increase blood flow to the skin, the blood vessels in the body first inform the brain of the elevated temperature. The brain then sends a message to blood vessels to dilate, increasing blood flow to the skin. The heart must also work harder to circulate the blood.
Some medicines and drugs can disrupt these processes resulting in a reduced ability to adjust to temperature changes. This article will help you learn more about the specific drugs that can harm you by putting you at higher risk for being overheated.
The body keeps cool by increasing blood flow to the skin and sweating. Listed below are drugs that disturb the body?s natural cooling mechanism and how they may cause you to overheat.
Some drugs reduce blood flow to your skin:
Some drugs both increase heat production and decrease blood flow to your skin:
Some drugs decrease sweating, leading to decreased heat loss and overheating:
Some drugs may cause dehydration:
Some medications may cloud your judgment and the need for action:
If you are taking any of these medicines or the medicines listed in Table 1 and Table 2 below, be aware that your ability to deal with the heat may be impaired.
| Table 1: General Drug Classes That Can Increase the Risk of Heat Injury |
Table 2: Medications with Potential for Hyperthermia (Overheating) or Reduced Heat Tolerance (The generic name is listed first, followed by some of the more common US trade names).
Remember! Do not stop taking any prescribed medication without first talking to your doctor
Note: This list does not include all medicines that could increase the risk of overheating.
|
|
|
Who is at risk for overheating?
What you can do to avoid overheating:
If you think you are overheated, follow the CDC's suggestions for treating heat-related illness.
Some medications may cause patients to burn more easily. This reaction is known as photosensitivity. Sunlight emits ultraviolet A rays. These ultraviolet a rays interact with some medicines to cause a photophotosensitivity reaction.
There are two types of photosensitivity reaction:
Table 3: Medications and herbs may cause photosensitivity reaction.(Generic name listed first, followed by some of the common trade names)
Remember! Do not stop taking any prescribed medication without first talking to your doctor.
Note: This list does not include all medicines that could cause photosensitivity reactions.
|
|
|
Some plants can also cause photosensitivity reactions. Photosensitivity reactions to plants are similar to those caused by medicines, but are most commonly a result of direct skin contact with sap or juice from the plants followed by exposure to sunlight rather than from eating the plants. The reaction is usually related to chemicals called furocoumarins in the plants. These reactions are most commonly reported in agricultural workers, cooks, bartenders, and grocery store workers, but also may be seen in gardeners and other inadvertently exposed individuals.
| Table 4. Plants Associated with Phototoxic Reactions. (Listed as common name followed by the Botanical name) Note: This list does not include all plants that could cause photosensitivity reactions |
Prevention is your best protection against photosensitivity reactions! Be aware of medications that have been associated with this reaction.
If you have questions regarding any of your medications, contact your physician, a pharmacist who knows you, or your local poison center 1-800-222-1222.
Prepared by Cincinnati Drug and Poison Information Center at (513) 636-5111 or 1-800-222-1222.
This article is a NetWellness exclusive.
Last Reviewed: May 02, 2011
|
Robert James Goetz, PharmD, DABAT Assistant Professor of Pharmacy Practice College of Medicine University of Cincinnati |
|
Earl G Siegel, PharmD Adjunct Professor, Pharmacy Practice Emeritus Professor of Emergency Medicine College of Medicine University of Cincinnati |