In America, the melanoma (skin cancer) rate is getting higher. You might be wondering, yes, it's increasing, but it's in America, what to do with Malaysia anyway?
Exposure to the sun's ultraviolet (UV) rays is a known risk factor in skin cancer. And well, I don't know whether you aware of not, Malaysia is exposed to strong sunlight all year long (only dumb won't notice that, by the way). In addition, Malaysia does not have such statistic team to count the rate of melanoma by the way (as I know, maybe there is, but I doubt that). The thing is, we, Malaysians, often living our life without foreseeing. We don't have the sense of risk.
Personally, I think, we are all at risk of the melanoma, ever since the ozone layer started to deplete.
Today, I don't want to talk about sunscreen. Instead, I want to talk about drugs that may increase your sensitivity to the sun, causing drug-induced photosensitivity.
Drug-induced photosensitivity is the development of cutaneous disease as a result of the combined effects of a chemical and light. Exposure to either the chemical or the light alone is not sufficient to induce the disease; however, when photoactivation of the chemical occurs, one or more cutaneous manifestations may arise.
Wavelengths within the UV-A (320-400 nm) range and, for certain compounds, within the visible range, are more likely to cause drug-induced photosensitivity reactions.
Occasionally UV-B (290-320 nm) can also be responsible for such effects.
Note that UV-B wavelengths are most efficient at causing sunburn and nonmelanoma skin cancer.
The drug-induced photosensitivity, can be differentiated into phototoxic and photoallergic reactions.
Phototoxic reactions occur because of the damaging effects of light-activated compounds on cell membranes and, in some instances, DNA.
While photoallergic reactions are cell-mediated immune responses to a light-activated compound.
Here, I want to focus more on phototoxic reactions, as they are the main culprit of increasing the risk of getting melanoma.
Many compounds have the potential to cause phototoxicity. Most have at least one resonating double bond or an aromatic ring that can absorb radiant energy. Most compounds are activated by wavelengths within the UV-A (320-400 nm) range.
Photoactivation of a compound results in the excitation of electrons from the stable singlet state to an excited triplet state. As excited-state electrons return to a more stable configuration, they transfer their energy to oxygen, leading to the formation of reactive oxygen intermediates. Reactive oxygen intermediates such as an oxygen singlet, superoxide anion, and hydrogen peroxide damage cell membranes and DNA.
This drug-induced photosensitivity reactions can occur in persons of any age, as long as you have eaten the 'right' drugs and exposed to enough sunlight to cause the photoactivation.
These are the examples the sunburn boosters:
frusemide and hydrochlorothiazide.
Tetracyclines drugs (doxycycline, tetracycline), Fluoroquinolones (ciprofloxacin, ofloxacin, levofloxacin), Sulfonamides [a.k.a. sulfa drugs] (trimethoprim)
isotretinoin and acitretin {note: they are available in some skin care products as well}
amiodarone
Sulfonylureas (glipizide and glibenclamide)
ibuprofen, ketoprofen
[These are just some examples, for more details, always check your medications with the pharmacists]
Even after you have stopped taking these drugs, their effects may linger, depending on the type of drug (the clearance of the drug from the body) and how long you've been taking it.
And one thing is: You don't even have to go out in the sun to get the drug-induced phototoxicity. You could easily get sunburned in a tanning salon!
Does using sunscreens help protect against photosensitivity?
The answer is unclear.
Sunscreens do lessen the effects of UV radiation, but some contain ingredients that themselves may cause phototoxicity in some people.
Also, most sunscreens protect only from UV-B, whereas most phototoxic compounds are activated by UV-A.
Sunscreens containing bergamot oil, sandalwood oil, benzophenones, PABA, cinnamates, salicylates, anthranilates, PSBA, mexenone, and oxybenzone can all cause phototoxicity.
Titanium dioxide seems to be the least likely sunscreen to cause phototoxicity.
So, to be safe, always ask the pharmacist about the effects of your medications on sun exposure.
Or at least, read the product leaflet (for the skin care products especially).
Personally, I think, we are all at risk of the melanoma, ever since the ozone layer started to deplete.
Today, I don't want to talk about sunscreen. Instead, I want to talk about drugs that may increase your sensitivity to the sun, causing drug-induced photosensitivity.
Wavelengths within the UV-A (320-400 nm) range and, for certain compounds, within the visible range, are more likely to cause drug-induced photosensitivity reactions.
Occasionally UV-B (290-320 nm) can also be responsible for such effects.
Note that UV-B wavelengths are most efficient at causing sunburn and nonmelanoma skin cancer.
The drug-induced photosensitivity, can be differentiated into phototoxic and photoallergic reactions.
Phototoxic reactions occur because of the damaging effects of light-activated compounds on cell membranes and, in some instances, DNA.
While photoallergic reactions are cell-mediated immune responses to a light-activated compound.
Here, I want to focus more on phototoxic reactions, as they are the main culprit of increasing the risk of getting melanoma.
Many compounds have the potential to cause phototoxicity. Most have at least one resonating double bond or an aromatic ring that can absorb radiant energy. Most compounds are activated by wavelengths within the UV-A (320-400 nm) range.
Photoactivation of a compound results in the excitation of electrons from the stable singlet state to an excited triplet state. As excited-state electrons return to a more stable configuration, they transfer their energy to oxygen, leading to the formation of reactive oxygen intermediates. Reactive oxygen intermediates such as an oxygen singlet, superoxide anion, and hydrogen peroxide damage cell membranes and DNA.
These are the examples the sunburn boosters:
[These are just some examples, for more details, always check your medications with the pharmacists]
Even after you have stopped taking these drugs, their effects may linger, depending on the type of drug (the clearance of the drug from the body) and how long you've been taking it.
And one thing is: You don't even have to go out in the sun to get the drug-induced phototoxicity. You could easily get sunburned in a tanning salon!
The answer is unclear.
Sunscreens do lessen the effects of UV radiation, but some contain ingredients that themselves may cause phototoxicity in some people.
Also, most sunscreens protect only from UV-B, whereas most phototoxic compounds are activated by UV-A.
Sunscreens containing bergamot oil, sandalwood oil, benzophenones, PABA, cinnamates, salicylates, anthranilates, PSBA, mexenone, and oxybenzone can all cause phototoxicity.
Titanium dioxide seems to be the least likely sunscreen to cause phototoxicity.
Or at least, read the product leaflet (for the skin care products especially).