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Pharmacy and Medications

Summer Heat Can Put You at Risk!

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.

Do not stop taking any prescribed medication without first talking to your doctor.

Reactions Due to Increased Heat

The body needs to maintain a relatively consistent temperature to function properly. Some medicines can block the natural ability of the body to adjust to changes in temperature. This can result in overheating.

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.

Some medicines and drugs can disrupt these processes resulting in a reduced ability to adjust to temperature changes.

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 drugs keep the body from increasing blood flow to the 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.

Table 1: General drug classes that can increase the risk of heat injury

  • Anticholinergic Medicines
  • Antihistamines
  • Anti-parkinsonian drugs
  • Beta Blockers
  • Decongestants
  • Diurectics
  • Phenothiazines
  • Tricyclic Antidepressants
  • Abuse drugs
  • Table 2: The following is table lists some medications that have the potential to cause hyperthermia (overheating) or reduce heat tolerance. (The generic name is listed first, followed by some of the more common US trade names)

  • Amoxapine - Asendin
  • Amphetamines - Adderal
  • Amitriptyline - Elavil
  • Aripiprazole - Abilify
  • Atenolol - Temormin
  • Belladonna Alkaloids (Donnatal)
  • Benztropine - Cogentin
  • Bumetanide - Bumex
  • Bupropion - Wellbutrin
  • Carvedilol - Coreg
  • Chlordiazepoxide/Amitriptyline - Limbitrol
  • Chlorpromazine - Thorazine
  • Clomipramine - Anafranil
  • Clozapine - Clozaril
  • Cocaine
  • Desipramine - Norpramin
  • Dextroamphetamine - Adderal
  • Dextromethorphan - Robitussin DM , others
  • Diphenhydramine - Benadryl
  • Diphenoxalate/Atropine - Lomotil
  • Doxepin - Sinequan
  • Flavoxate - Lavoxate
  • Furosemide - Lasix
  • Haloperidol - Haldol
  • Hydrochlorothiazide - Hydrodiuril, HCTZ
  • Hydroxyzine - Atarax, Vistaril
  • Hyoscyamine - Levsin
  • Imipramine - Tofranil
  • Indapamide - Lozol
  • Ketamine - Ketalar
  • Labetalol - Normodyne
  • Levodopa - L dopa,
  • Levodopa/carbidopa
  • Lisinopril/hydrochlorothiazide - Prinzide
  • Lithium - Lithobid, Eskalith
  • Loxapine - Loxitane
  • MDMA
  • Methamphetamine
  • Methylphenidate - Ritalin, Concerta, Others
  • Metoclopramide - Reglan
  • Metoprolol - Toprol
  • Molindone - Moban
  • Morphine - MS- Contin, Kadian
  • Nitrous oxide
  • Nortriptyline - Pamelor
  • Olanzapine - Zyprexa
  • Olanzapine/fluoxetine - Symbyax
  • Oxybutynin - Ditropan
  • Oxcarbazepine (Trileptal)
  • Perphenazine - Trilafon
  • Phentermine - Fastin , Others
  • Procainamide - Pronestyl
  • Propantheline - Pro-Banthine
  • Propranolol - Inderal
  • Propylhexedrine
  • Pseudoephedrine (Sudafed, others)
  • Quetiapine - Seroquel
  • Risperidone - Risperdal
  • Thioridazine - Mellaril
  • Thiothixine - Navane
  • Topiramate - Topamax
  • Tranylcypromine - Parnate
  • Trazodone - Desyrel
  • Triamterene - Dyrenium
  • Triamterene/ Hydrochlorothiazide - Maxide, Dyazide
  • Trifluoperazine - Stelazine
  • Trihexyphenidyl - Artane
  • Trimeprazine
  • Ziprasidone - Geodon
  • Zonisamide - Zonegran

  • Note: This list is not all inclusive.

    Overheating can be a medical emergency

    The elderly and young children are inherently at higher risk of overheating.

    Patients who are isolated for whatever reason are at an increased risk.

    Patients of any age suffering with mental illness are also at high risk.

    Physical activity, fluid intake, clothing and humidity affect your body's ability to maintain a safe temperature.

    Even if you are not taking any medications, it is a good idea to wear lightweight clothing, drink plenty of fluids, stay in the shade and avoid heavy activity when it is hot outside.

    When it is hot, move to a cooler area.

    Try to spend some time in air-conditioned spaces like shopping malls.

    Do not exercise or work during the hottest parts of the day.

    The combination of high heat and high humidity increases the risk of overheating.

    Try to plan outdoor activities for the cooler parts of the day.

    Wear lighter clothing.

    Shower frequently.

    Reactions Due to Exposure to the Sun

    Some drugs may cause patients to burn more easily. This reaction is known as photosensitivity. There are two types of photosensitivity reaction: Phototoxicity and photo allergy.

  • Sunlight emits ultraviolet A rays and these are what cause the phototoxic reaction. Phototoxicity is the most common form of photosensivity reaction. This reaction causes redness and tenderness of the skin and generally occurs 2 to 6 hours after being out in the sun. The reaction may be severe enough to cause blistering.
  • A photoallergic reaction in a less common form of photosensitivity. A photoallergic reaction usually involves itching and scaling of the skin, and generally occurs 5-10 days after exposure to ultraviolet A. The reaction may be severe.
  • Table 3: The following are some of the herbs and medications that may potentially cause photosensitivity reaction. (Generic name listed first, followed by some of the common trade names)

    Note: This list is not all inclusive.
  • acetazolamide -- Diamox
  • acetohexamide - Dimelor
  • alprazolam -- Xanax
  • amantadine -- Symmetrel
  • amiodarone -- Cordarone
  • amitriptyline --Elavil
  • amobarbital -- Amytal
  • Amoxapine - Asendin
  • azithromycin -- Zithromax
  • benazapril - Lotensin
  • benzocaine - found in many Solarcaine products
  • butalbital - found in Fioricet and Fiorinal
  • captopril -- Capoten
  • carbamazepine -- Tegretol
  • celecoxib - Celebrex
  • carbinoxamine
  • chlordiazepoxide -- Librium
  • chlorhexidine
  • chloroquine
  • chlorothiazide -- Diuril
  • chlorpromazine -- Thorazine
  • chlorthalidone -- Hygroton
  • ciprofloxacin - Cipro
  • clozapine -- Clozaril
  • co-trimoxazole -- also known as Bactrim or Septra
  • cyproheptadine -- Periactin
  • dacarbazine
  • dapsone
  • diphenhydramine -- Benadryl
  • divalproex sodium -- Depakote
  • doxepin -- Sinequan
  • doxycycline -- Vibramycin
  • enalapril - Vasotec
  • estrogen/progestin - found in birth control pills
  • fenofibrate -- Lipidil
  • floxuridine
  • flucystosine
  • fluorouracil
  • fluphenazine - Prolixin
  • fluvoxamine -- Luvox
  • fosinopril - Monopril
  • furosemide -- Lasix
  • ganciclovir -- Cytovene
  • glipizide -- Glucotrol
  • glyburide -- Diabeta, Micronase
  • griseofulvin
  • haloperidol -- Haldol
  • hydrochlorthiazide
  • ibuprofen -- Advil, Motrin
  • imipramine - Tofranil
  • indapamide -- Lozol
  • interferon-beta
  • isoniazid
  • isotretinoin -- Accutane
  • ketoprofen - Actron, Orudis
  • leuprolide
  • levofloxacin -- Levaquin
  • lisinopril - Prinovil
  • lincomycin
  • lomefloxacin
  • losartan - Cozaar, Hyzaar
  • methyldopa Aldomet®, Others
  • methyldopate
  • metolazone -- Zaroxolyn
  • minocycline -- Minocin
  • mirtazapine -- Remeron
  • nabumetone -- Relafen
  • nalidixic acid
  • nifedipine -- Procardia
  • norfloxacin _ Noroxin
  • nortriptyline -- Pamelor
  • ofloxacin -- Floxin
  • omeprazole -- Prilosec
  • oxaprozin -- Daypro
  • paroxetine -- Paxil
  • pentobarbital
  • perphenazine -- Trilafon
  • phenelzine
  • phenobarbital
  • phenylbutazone
  • phenytoin -- Dilantin
  • piroxicam - Feldene
  • Porfimer - Photofrin
  • procaine
  • prochlorperazine -- Compazine
  • promazine
  • promethazine -- Phenergan
  • protriptyline
  • pyrazinamide
  • pyridoxine - Vitmain B6
  • pyrimethamine
  • quinidine
  • quinine
  • risperidone -- Risperdal
  • salicylates - Aspirin , others
  • saquinavir -- Invirase
  • secobarbital
  • selegiline -- Eldepryl
  • sertraline -- Zoloft
  • silver sulfadiazine - Silvadene
  • sparfloxacin -- Zagam
  • St. John's Wort
  • Sulfa drugs
  • sulfamethoxazole -- Bactrim and Septra
  • sulfasalazine - Azulfidine
  • tetracycline
  • thiethylperazine
  • thioridazine - Mellaril
  • thiothixene -- Navane
  • trazodone -- Desyrel
  • tretinoin -- Retin-A
  • triamterene -- Dyazide
  • trifluoperazine -- Stelazine
  • trimethoprim --Bactrim and Septra
  • trovafloxacin -- Trovan
  • valproic acid -- Depakene
  • vinblastine -- Velban
  • Prevention is your best protection against photosensitivity. Be aware of medications that have been associated with this reaction.

    If you have questions regarding any of your medications, contact your physician, a pharmicist 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.

    For more information:

    Go to the Pharmacy and Medications health topic, where you can:

    This article is a NetWellness exclusive. NetWellness Article

    Last Reviewed: Jul 25, 2006

    Cincinnati Children’s Hospital Medical Center Robert James Goetz, PharmD, DABAT
    Assistant Professor of Pharmacy Practice
    Drug and Poison Information Center
    Cincinnati Children’s Hospital Medical Center
    University of Cincinnati

    Cincinnati Children’s Hospital Medical Center Earl Siegel, PharmD
    Professor of Emergency Medicine
    Drug and Poison Information Center
    Cincinnati Children’s Hospital Medical Center
    University of Cincinnati