Photosensitivity - Light Sensitive Drugs - Learning Objectives

• Do medications react to light?
• 3 types of photosensitivity.
• How natural and artificial light affect photosensitivity.

2000 different medications are light reactive

Medications can react to light, increasing skin sensitivity and affecting potency.

• By changing the effects of drug.
  
• By changing your skin sensitivity to light.
• By reacting to light with a pre-programmed effect used to treat some cancers and skin disorders.
  

Research the drugs you take before spending time with exposure to bright light indoors or outdoors. [1]

• Read all medication literature.
• Consult your doctor and pharmacist.

There are many types of Photosensitivity

1. Your body becomes more sensitive to light from medication or health conditions.
Phototoxic reactions
In phototoxic reactions, the drug may become activated by exposure to sunlight and cause damage to the skin.

2. Your medications can react to light.
Photoallergic reactions
In photoallergic reactions, the ultraviolet exposure changes the structure of the drug so that is seen by the body's immune system as an invader (antigen).

3. Your medications activate to specific wavelengths.
Light-Activated Drugs
A new technique that uses light to activate chemotherapy drugs in specific cells shows promise as a way to improve the effectiveness of cancer therapies while preventing severe side effects, according to a study published July 9, 2015 in Cell. [3]

UV, why is it important?

Your skin is your biggest organ! Your skin is sensitive to light, medications can alter this sensitivity, and light can alter the efficacy of the drug.
Eye protection is important, Ophthalmologists recommend that you wear 99 percent and higher UV (ultraviolet radiation)-absorbent sunglasses and a brimmed hat whenever you're in the sun for long periods of time. Proper sunglasses are key to protecting your eyes from sun-related damage, and they should be worn anytime you are outdoors, particularly under these circumstances:

• During the summer, when the level of ultraviolet radiation (UVA and UVB) is at least three time higher than during the winter;
• When at the beach or in the water;
• When participating in winter sports, especially at high altitudes;
• When using medications that can cause sensitivity to light (photosensitivity).

The best sunglasses offer 100 percent UV absorption, are of the best optical quality and are impact resistant. [1]

Snow, water, high elevations increase exposure to light.

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Footnotes

1. https://www.dhs.wisconsin.gov/radiation/medications.htm#Sources
2. http://www.ncbi.nlm.nih.gov/pubmed/10604793
3. http://www.eurekalert.org/pub_releases/2015-07/cp-ntf070215.php
   

Photo Credits

• Mammoth Mountain by Trish Odenthal
• Pills by e-Magine Art
  

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