Q&A with Dr. Kiskila: Why Does Heat Make Some Medications More Complicated?

Hot weather affects everyone differently, but some medications can make the body’s response to heat more complicated. Certain medicines may influence sweating, hydration, sun sensitivity, or the body’s ability to regulate temperature.

We asked Dr. Nathan Kiskila to explain what patients should know about medications and summer heat, who may be more vulnerable, and why it is important not to stop a medication without speaking with a healthcare professional.

Question: Why can hot weather be more complicated for people taking certain medications?

Dr. Kiskila: Your body has several ways of managing heat. Sweating helps cool the skin, blood flow changes help release heat, and thirst encourages you to replace lost fluids. Some medications can affect one or more of those processes. For example, a medicine may reduce sweating, increase fluid loss, affect thirst, or make it harder for the body to regulate temperature efficiently. Other medications may increase sensitivity to sunlight. That does not mean everyone taking these medications will have a problem. It simply means some people may need to be more aware of how they feel during hot weather.

Question: What types of medications can affect sweating?

Dr. Kiskila: Certain medications can reduce the body’s ability to sweat normally. Since sweating is one of the body’s primary cooling mechanisms, reduced sweating may make it harder to release heat. This effect can occur with some medications that have anticholinergic properties, as well as certain medicines used for conditions such as allergies, bladder symptoms, mood disorders, or other health concerns. The important point is that medication effects vary widely. Patients should not assume a medication is unsafe simply because it falls into a broad category. A pharmacist or healthcare professional can review a specific medication list and explain individual risks.

Question: Can medications increase the risk of dehydration?

Dr. Kiskila: Yes, some can. Certain medications increase urination or otherwise affect fluid and electrolyte balance. During hot weather, when the body is already losing fluid through sweat, dehydration may develop more easily. Symptoms of dehydration can include:

• Increased thirst
  
• Dry mouth
  
• Headache
  
• Fatigue
  
• Dizziness or lightheadedness
  
• Darker urine
  
• Urinating less often

People who exercise outdoors, work in the heat, or spend long periods outside may need to pay closer attention to hydration. At the same time, drinking excessive amounts of water is not appropriate for everyone. Some people with heart, kidney or other medical conditions may have specific fluid recommendations. If you are unsure, ask your healthcare professional what is appropriate for you.

Question: What about medications that make skin more sensitive to the sun?

Dr. Kiskila: Some medications can cause photosensitivity, meaning the skin reacts more strongly to ultraviolet radiation. A person may burn more quickly or develop a rash after sun exposure that would not normally cause a problem. Photosensitivity can occur with certain antibiotics, acne treatments, anti-inflammatory medications, and other prescription or over-the-counter medicines. Patients can review medication labels and ask a pharmacist whether sun sensitivity is a known concern. When appropriate, protective clothing, shade, and broad-spectrum sunscreen can help reduce exposure.

Question: Can medication affect the body’s ability to regulate temperature?

Dr. Kiskila: In some cases, yes. The body’s temperature regulation system depends on the nervous system, circulation, sweating and fluid balance. Medications that affect these systems may change how efficiently someone responds to heat. This becomes especially important during prolonged heat exposure, outdoor exercise or heat waves. Older adults may also be more vulnerable because the body’s response to heat can become less efficient with age, and many older adults take multiple medications.

Question: Are children also at risk?

Dr. Kiskila: Children can be vulnerable to heat because they may not recognize early symptoms or communicate what they are feeling. If a child takes regular medication, parents and caregivers can ask the child’s healthcare professional or pharmacist whether heat, hydration, or sun exposure requires any special precautions. It is also important to remember that children should never be left in a parked vehicle, even briefly. Vehicle temperatures can rise dangerously fast.

Question: What are the warning signs that heat is becoming a problem?

Dr. Kiskila: Early heat-related symptoms may include:

• Heavy sweating
  
• Weakness or unusual fatigue
  
• Headache
  
• Nausea
  
• Muscle cramps
  
• Dizziness
  
• Increased thirst
  
• Feeling faint

More serious symptoms can include confusion, collapse, loss of consciousness, or very high body temperature. These may indicate a medical emergency. If someone becomes confused, loses consciousness or shows signs of severe heat illness, call 9-1-1 and begin cooling measures while waiting for emergency help.

Question: Should someone stop taking a medication during hot weather?

Dr. Kiskila: No one should stop, skip or change a prescribed medication simply because the weather is hot without first speaking with a qualified healthcare professional. Abruptly stopping certain medications can cause serious problems. If you are concerned about how a medication interacts with heat, the best approach is to speak with your prescribing clinician or pharmacist. They can review the specific medication, dosage, medical history and individual risk factors.

Question: What can people do to stay safer during hot weather?

Dr. Kiskila: Start by knowing your medications. Read labels, review warnings and ask questions if you are unsure. Other practical steps may include:

• Stay hydrated according to your individual health needs
• Limit strenuous activity during the hottest part of the day
  
• Take breaks in air-conditioned or shaded areas
  
• Wear lightweight, breathable clothing
  
• Use sun protection when taking medications associated with photosensitivity
  
• Pay attention to dizziness, weakness, headache or unusual fatigue
  
• Check on older adults and others who may be more vulnerable during extreme heat

Most importantly, do not ignore symptoms that are worsening.

Question: When should someone seek medical care?

Dr. Kiskila: Medical evaluation may be appropriate for persistent dizziness, vomiting, worsening weakness, signs of dehydration, or symptoms that do not improve after moving to a cooler environment and resting. Severe confusion, fainting, loss of consciousness, seizures or suspected heat stroke require emergency care. Call 911.

Heat can make certain medications more complicated by affecting sweating, hydration, sun sensitivity or the body’s ability to regulate temperature. The level of risk depends on the specific medication, the person’s health and the amount of heat exposure.

Patients should never stop or change a prescribed medication on their own because of hot weather. If you have questions about a specific medicine, speak with your healthcare professional or pharmacist. And if heat-related symptoms develop this summer, Marque Urgent Care is here to help with life’s everyday urgencies.