During the summer months exposure to the sun is practically unavoidable. Firstly, because daylight hours increase and secondly, because it is time for the beach, pool, terrace, camping or outdoor sports.
And although we know that it is always essential, we probably do not take into account that there are certain medications that can react when exposed to sunlight.
chronic treatmentstransient illnesses, suppose the taking that when exposing them or exposing ourselves while we take them to the sun, can have consequences.
Paula Mateosa pharmacist from the Technical Services of the General Council of Pharmacists, explains the first question that must be taken into account when talking about sun and medicines.
First of all, says Mateos, let’s distinguish between a photosensitive drug and a photosensitizing drug.
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The photosensitive drugs are those medicines light sensitive. In other words, light can cause changes in its appearance, decrease its pharmacological activity, or its use may cause adverse reactions.
“To avoid deterioration, they must be protected from light (both natural and artificial) and, for this reason, they are usually presented in opaque containers,” says the pharmacist.
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The photosensitizing drugs are those drugs that combined with ultraviolet radiation, they cause an abnormal skin reaction.
To make them easily identifiable, on some occasions they have the pictogram indicating so printed on their packaging.
Once this difference is clarified, it must be clear that Precautions must be taken when storing and transporting photosensitive drugs.
Regarding the medicines photosensitizers they can Paula Mateos details that they can “provoke two types of reactions: photo-toxic and photo-allergic”.
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The reactions more frequent are the phototoxic. “They are generally produced by orally administered photosensitizing drugs.”
They are reactions in which the immune system does not mediate and usually appear immediately after exposure to the sun. They usually occur in people exposed to high doses of the drug.
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The photoallergic reactions are less frequent and are generally due to photosensitizing drugs administered topically.
These reactions are always related to the immune system and their symptoms appear between 12 and 72 hours after exposure to the sun. They can appear with a patient’s exposure to low doses of the drug.
Normally, the phototoxic reaction produces lesions that have the appearance of exaggerated sunburnwith burning sensation and formation of microvesicles or urticaria.
“Instead, photoallergic reaction It manifests itself in a similar way to contact dermatitis, with an eczematous rash, edema, and intense pruritus,” the expert details.
Although the photoallergic reaction occurs on the surface exposed to the sun, over time it can spread to protected areas of the skin.
What are photosensitizing drugs?
There are a large number of photosensitizing drugs. The pharmacist reviews some very common dispensing in the pharmacy:
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Antidepressants (such as fluoxetine or paroxetine).
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Antihistamines (such as ebastine, loratadine, or cetirizine).
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Topical antihistamine creams such as diphenhydramine, used for mosquito bites.
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Non-steroidal anti-inflammatory drugs, such as ibuprofen, both topical and oral.
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Antihypertensives such as enalapril, losartan or amlodipine.
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Retinoids, such as isotretinoin or retinoic acid.
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oral contraceptives
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Benzodiazepines
But in addition to the drugs themselves, “there are also cosmetic products, mainly with retinol or glycolic acid, which can cause photosensitivity reactions,” adds Mateos.
In addition, it is interesting to remember that there are ingredients such as some dyes, perfumes or essences, lemon or lavender, which can also produce this type of reaction.
In any case, to avoid these photosensitivity reactions, the pharmacy expert gives us some recommendations to follow this summer:
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Whenever possible, these medications should be taken at night.
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Always use sunscreen in sufficient quantity and with a high sun protection factor; renewing the application every 2 hours and after each bath.
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And avoid exposure to the sun between 12 and 16 hours.
Finally, and since we are not all experts in pharmacology, the General Council of Official Colleges of Pharmacists It has a computer application that allows you to consult all the necessary information about medicines.
This database “not only always includes the aforementioned photosensitivity pictogram in the tab of all photosensitizing medications, but also allows a free search of all these medications by selecting in the section Warnings the characteristic drug that can cause a photosensitivity reaction,” explains Mateos.