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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 - 320 nanometers
- UV-A: 340 - 400 nanometers (UV-A I, or "Far"
UV-A)
- UV-A: 320 -
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. The
UVEX lens chart
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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.)
- 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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This article is presented as part of an ongoing effort to present other views outside of, as well as within, the online vampire community. As such, the views and attitudes contained in this article are entirely those of the author(s), and may not necessarily be shared by SphynxCatVP. The webmaster is not under obligation to update or otherwise keep current the contents of this article. Most importantly, only you can decide for yourself whether this article or any of the author(s) other views are useful or applicable to you - use your own reasoning and judgement.
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