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Photosensitivity can happen for many reasons, not just because of vampiric
tendencies. Please take the time to rule out the mundane causes - wouldn't
you feel better knowing that you have a medical condition that can be
treated and being able to get it treated before it was too late? This
article is broken down into the following sections:
(If you're looking for tips on how to deal with photosensitivity, that's
covered here.)
The degree of photosensitivity varies among individuals. Not everyone
who uses an item containing photoreactive agents will have a photoreaction.
In fact, a person who has a photoreaction after a single exposure to a
photoreactive agent may not react to the same agent after repeated exposures.
OTOH, people who are allergic to one chemical may develop photosensitivity
to another related chemical to which they would normally not be photosensitive.
In such a case, a photosensitive reaction to one chemical increases a
person's chance for a reaction to a second.
Although those with fair skin are more susceptible to photosensitizing,
it is not uncommon for dark-skinned individuals to have chronic photodermatitis
(light-related skin problems). Before going out into the sun, it's a good
idea to check with your doctor to see if any of the medications you're
taking is likely to cause problems and decide how to best avoid such reactions.
Read the labels of OTC drugs and note if they are likely to be photosensitizing
- the label may not specify that it is photosensitizing, but if you're
familiar with what's on the chemical list, it'll be easier to weed them
out. If you get symptoms after being out in the sun, you may want to consider
what drugs and chemicals you are using and contact your doctor or other
medical professional immediately about advice.
UV WAVELENGTHS
Did you know ultraviolet rays are classified
into three different wavelength sizes? (Maybe more, but I've only heard
about three.) They run approximately like this: :
- UV-C: 200 - 280 nanometers (Commonly
given off by welding equipment)
- UV-B: 290 - 315 nanometers
- UV-A: 340 - 400 nanometers (UV-A I,
or "Far" UV-A)
- UV-A: 315
- 340 nanometers (UV-A II, or "Near" UV-A)
The UV-A / UV-B wavelengths are commonly referred
to on packages of sunscreen lotion (and now you know the wavelengths!)
but UV-C is a factor as well - especially with exposure to sunlight
and full-spectrum light sources - even if it's not as commonly known.
UV-C is also given off by various types of welding equipment. Those
of you who may be welding for a living, or know someone who is, will
need to take this into account.
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TYPES OF PHOTOSENSITIVE
REACTIONS
Photoreactions
Chemicals that produce a photoreaction (reaction
with exposure to UV light) are called photoreactive agents, or more
commonly, photosensitizers. After exposure to UV radiation either from
natural sunlight or an artificial source such as tanning booths or bug
zappers, these photosensitizers cause chemical changes that increase
a person's sensitivity to light, causing the person to become photosensitized.
Photoreactive agents can cause both acute and chronic effects, which
include the following (this is not an exhaustive list):
Acute effects: Exaggerated
sunburn-like conditions, eye burn, mild allergic reactions, hives,
abnormal reddening of the skin, and eczema-like rashes with itching,
swelling, blistering, oozing and scaling of the skin.
Chronic effects: Premature
skin aging, stronger allergic reactions, cataracts, blood vessel
damage, a weakened immune system, and skin cancer.
Photosensitizers can cause either photoallergic
or phototoxic reactions. Because drug-induced photosensitivity disorder
symptoms mimic sunburns, rashes and allergic reactions, many cases go
unreported. Also, although research has shown that the numbers of photosensitized
individuals may be high, most people do not associate the sun's light
with the development of their skin eruptions.
Photoreactive products can also aggravate existing
skin problems like eczema, herpes, psoriasis and acne, and can inflame
scar tissue. They can also precipitate or worsen autoimmune diseases,
such as lupus erythematosus and rheumatoid arthritis, in which the body's
immune system mistakenly destroys itself.
Photoallergies
This type of reaction appears as a rash or reddened
area of skin, sometimes with blistering or swelling. It is caused by
a change in one's immune system (which can be due to any one of many
different factors), and the symptoms appear every time the skin is exposed
to sunlight. In photoallergic reactions, which generally occur due to
medications applied to the skin, UV light may structurally change the
drug (a light-induced chemical reaction) causing the skin to produce
antibodies. The result is an allergic reaction. (An example of this
type of allergic reaction would be a reaction to poison ivy, although
the poison ivy problem is not light based.) Symptoms can appear within
20 seconds after sun exposure, but can also be delayed - one photoallergic
reaction documented in a medical magazine on Contact Dermatitis took
three months to develop. (That was a reaction to a topical NSAID - Non
Steroidal Anti
Inflammatory Drug
- called Suprofen, not approved for use in the USA.)
Phototoxicity
Phototoxic reactions, which do not affect the
body's immune system, are more common than photoallergic reactions.
These reactions can occur in response to injected, oral or topically
applied medications. Phototoxic reactions look and feel like an extreme
sunburn. They are usually the result of a reaction between a certain
chemical (medicines, shampoos, etc.) and sunlight.
In a phototoxic reaction, the drug(s) absorb
the energy from UV light and releases the energy into the skin, causing
skin cell damage or death. The reason occurs from within a few minutes
to several hours after UV light exposure. Though sunburn-like symptoms
appear only on the parts of the body exposed to UV radiation, resulting
skin damage can persist, with or without continuing exposure to UV rays.
In some cases, people exposed to photoallergens may continue
to have phototoxic skin eruptions up to 20 years after discontinuing
use of the offending product, even though they avoided further exposure
to the photoallergens. Yeouch!
Because drug induced photosensitivity disorder
symptoms mimic sunburns, rashes and allergic reactions, many cases go
unreported. Also, although research has shown that the numbers of photosensitized
individuals may be high, most people do not associate the sun's light
with the development of their skin eruptions.
Photophobia
This is a a condition of abnormal sensitivity
to light (i.e., the amount of light entering the eye); usually, the
iris is unable to constrict enough to reduce the light entering the
eye to a comfortable level. . This condition is normally a symptom of
associated disorders or disease (e.g., corneal inflammation, aphakia,
iritis, or ocular albinism). Some drugs and/or poisons also can cause
photophobia by causing pupil dilation (notably, amphetamines and antihistamines,
cannabis and cocaine, atropine, scopolamine, mydriotics and cycloplegics
(these are drugs used to dilate the pupils during an eye exam - Mydriatics
only dilate the pupils; cycloplegics dilate the pupils and paralyze
the muscles used in accommodation - photophobia is a temporary condition
following the use of these drugs and lasts until the drug wears off,
usually several hours) and strychnine). Sometimes glasses with
anti-reflective coatings will help - but not always! I tried anti-reflective
coatings on a pair of new glasses, and it only made the problem worse.
Anti-reflective coatings (at least from this particular company) reduce
the glare seen on your lens, that's all. If your photophobia is triggered
by glare, then it may help. If your photophobia is due to purely the
amount of light, then it will only make the problem worse because it
reduces the glare by allowing more light through the lens.
Photophobia can be the body's way of attempting
to let the eye heal after a recent injury, as well, see "Corneal
Abrasion" in the physical conditions section.
FWIW, I don't particularly agree with "photoPHOBIA"
as an accurate term - just because something hurts doesn't necessarily
mean a person is afraid of it. But I don't expect the medical community
to change this just because some "weird person" comes up with
a reason not to use it. *laughs*
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THE ROLE OF GENETICS
AND ENVIRONMENT
And no, I don't mean "vampire genes". :)
Certain people are genetically predisposed towards photosensitivity
in varying degrees, such as if you have pale skin and/or light colored
eyes. Someone who's Swedish, for instance, will *tend to* be much more
sensitive than someone who's from the Mediterranean. If you work shifts
that don't expose you to a lot of sunlight (such as working night shift
as a security guard) you may be more sensitive just because you haven't
been out in the sun as much. Pale skinned people ARE much more prone
to sunburn - thus, a higher SPF sunscreen is usually recommended for
them as a result. Not much can be done about this, except to protect
your skin and eyes.
If you always wear sunglasses when you go out during the day, your
eyes will become more sensitive because they're not exposed to as much
light. As long as the sunglasses block 100% of UV rays, this is not
necessarily a bad thing!
Some cases of glaucoma or cataracts have been linked to excessive exposure
to UV rays, particularly from the sun or in tanning booths. (Hence why
I say wearing sunglasses all day isn't necessarily a bad thing. *grins*)
It just means you need to keep wearing the sunglasses (which medical
folks are now strongly hinting that you should be wearing anyway) or
if you're bound and determined to fry your eyes :) just force yourself
to get used to the bright shiny yellow thing in the sky again.
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EXAMPLE MEDICATIONS
THAT CAN CAUSE PHOTOSENSITIVE REACTIONS
|
BRAND NAME
|
GENERIC / CHEMICAL NAME
|
THERAPEUTIC CLASS
|
| Azulfidine |
sulfasalazine |
antiarthritic, antibiotic. |
| Bactrim |
trimethoprim |
antibiotic |
| Cordarone |
Amiodarone |
antyarrhythmic |
| Crystodign |
digitoxin |
antiarrhythmic (heart medication) |
| Diabinese |
chlorpropamide |
antidiabetic (oral) |
| Doxycycline |
Doxycycline |
Tetracycline class antibiotic |
| Duraquin |
quinidine |
antiarrhythmic |
| Feldane |
piroxicam |
NSAID, antiarthritic |
| Motrin |
Ibuprofin |
NSAID, antiarthritic |
| Orinase |
tolbutamide |
antidiabetic |
| Phenergan |
promethazine |
antihistamine |
| Tolinase |
tolazamide |
antidiabetic |
| Sinequan |
doxepin |
antidepressant |
| Vibramycin |
doxycycline |
antibiotic |
This is by no means an exhaustive list - and you can find other lists
of photosensitizer drugs here:
 Focus
Newsletter: Medications, side effects, and your eyes Nighthaven
article on photosensitivity
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SOME COMMON ITEMS THAT
MAY CAUSE PHOTOSENSITIVITY IN SOME PEOPLE
- Sunscreens containing: PABA, bergamot oil, sandalwood oil, benzophenones,
cinnamates, salicylates, anthranilates, PSBA, mexenone and oxybenzone.
(Some information on various sunscreen chemicals is here
or you can see my article on sunscreens.)
- deodorants
- antibacterial soaps
- artificial sweeteners
- fluorescent brightening agents for cellulose, nylon and wool fibers
- napthalene (mothballs)
- petroleum products (such as petroleum jelly, "Vaseline"
being an example)
- cadmium sulfide (a chemical injected into the skin during tattooing)
- Vitamin deficiency
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DISEASES, GENETIC DISORDERS
AND OTHER PHYSICAL CONDITIONS WITH PHOTOSENSITIVITY
These links are courtesy of the E-Medicine website, and will have
some medical terminology. This is not a complete list, this is only a
jumpoff point.
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TANNING BOOTHS
Tanning booths and the use of indoor tanning products (sometimes called
the "tan in a bottle" method) can be more of a problem than
natural sunlight, and this is true with photosensitivity reactions as
well as in general. FDA enforces policies in which sunlamp product manufacturers
much develop an exposure schedule and establish a minimum recommended
exposure time (and therefore the maximum time interval) based on the
characteristics of their particular products. This information must
appear on the products label and in no way is to be considered as a
safe limit.
The FDA warns that some tanning operators may claim that UV-A sunlamps
are safer than the sun and UV-B lamps. This is not true. In fact, exposure
to the UV radiation from sunlamps adds to the total amont of UV radiation
you get from the sun during your lifetime, further increasing your risk
for cancer, and increasing the amount of visual aging you have later
on (i.e., wrinkles, thickened "alligator feel" skin, spots,
etc.)
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topics; however, no warranty whatsoever is made that any of the articles
are accurate - and even if a statement made about medical matters is
accurate, it may not apply to you or your symptoms. These
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- nothing on this site should be construed as an attempt to offer or
render a medical opinion or otherwise engage in the practice of medicine.
Even though the authors may be capable of
doing extensive research, it must be understood that neither SphynxCatVP,
nor the rest of the contributors, are doctors, despite the presence
of any books of the medical profession in the personal libraries of
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in whole, by nonprofessionals. Consequently, there is absolutely no
guarantee that any statement contained or cited in an article touching
on medical matters is true, precise, or up-to-date.
At best, you can use the article to strike
up a conversation with your doctor or other medical professional ABOUT
your symptoms, and share any concerns you may have for them to investigate.
The medical information provided by this site is of a general nature
and CANNOT legally be considered a substitute for the advice of a medical
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