Our readers know that here at Dr Seb we take allergies very seriously and we worked hard to bring our readers the most relevant and up-to-date information about allergies and the ways they can be treated and managed. This time, we have a special treat for our fellow health enthusiast – an article detailing seven strange, unheard of and at times straight out bizarre allergies that really exist.
What’s on this page?
But, make no mistake, people affected by these rare allergies are just as much at risk as anyone else and in some cases probably even more. So, let’s start with some basic facts, before diving deep into these uncommon allergies that have really been documented.
Allergies: A quick fact check
Allergies are relatively common and their prevalence seems to increase by the day with roughly a third of the global population experiencing allergic reactions over the course of their lives. Out of those 30% documented allergy cases, the vast majority is diagnosed with a form of common allergy, for example, allergies to animal dander, hay fever or allergic rhinitis, insect bites allergies and similar. In addition to this, the majority of those is located in the industrialised, western societies.
However, a small fraction of those affected by allergies is struggling with rare and lesser-known allergies which can sometimes sound strange and outright bizarre. Sadly, the rarity of these allergies makes them only moderately understood and the treatment options are mostly general and non-specific.
Allergies and proteins: A vital link
A vast majority of all allergies are caused by different types of proteins, so it is at least technically possible to develop an allergy to any given substance that contains proteins. However, in practice this seldom occurs and allergies still tend to be caused by a much more limited array of allergens and irritants.
The reason why allergies occur is still largely unknown and widely debated in the medical community. As of now, it seems that there is an ever-growing body of evidence indicating that the hypothesis about the genetic and hereditary causes of allergies might be the right one. While environment and lifestyle certainly play a role in developing allergies, it seems that genetics can be a major factor in most cases, and this is especially true when it comes to rare allergies.
Allergies and asthma
A link between allergies and asthma is well known and there are some medical experts that think the same might be true for the rarer allergies too. And while empirical research is still very limited, there are some indications that this might be true. It seems that genetic predispositions for allergies, asthma, eczema and hay fever are all closely connected and thus run in families. However, having a genetic predisposition to any given health condition doesn’t mean that you will necessarily develop it.
Some of the most rare allergies
Now when all the basic facts regarding allergies have been covered, we can dive into examining the rare ones, while also discussing the effective coping and managing strategies.
Semen allergy (Seminal plasma hypersensitivity)
As was mentioned before, allergies are most commonly caused by different proteins and some people can even exhibit an allergic reaction to proteins naturally present in the male sperm. While this is a very rare allergy and research into it is more than limited, there are some indications that roughly 12% of women might be affected. Naturally, the symptoms of a reaction will manifest following a sexual intercourse during which sperm came into contact with the vagina. The usual symptoms include:
- Redness
- Swelling
- Itching
- Painful or burning sensation in the vagina
As these symptoms are common for a number of sexually transmitted infections as well as vaginitis, bacterial vaginosis and fungal infections of the vagina, the condition can be easily misdiagnosed and left untreated. However, one of the most direct signs that this might be the cause of troubles is the direct link between manifestation of symptoms and the use of condom. Of course, if the symptoms occur only after unprotected intercourse, then sperm allergy might be the culprit.
This type of allergy can put strain on the relationship and especially so when a couple is trying to conceive. While this allergy isn’t likely to produce any dangerous symptoms, nor will it affect woman’s fertility, artificial insemination might be recommended for women who are affected by the more severe forms of this rare allergy.
Water allergy (Aquagenic urticarial)
One of the rarest forms of allergy known to modern medicine, water allergy is exactly what it sounds like – an allergic reaction caused by water. When individuals affected come into contact with water, symptoms such as hives, rash or angioedema will manifest, with the rash being particularly uncomfortable and even painful in more severe cases. Even more frightening, aquagenic urticarial doesn’t have to be caused by one specific type of water like, for example, chlorinated or salt water, it can occur in response to exposure to any type of water, in more severe cases, even sweat and tears.
This rare allergy, often said to be ‘the rarest of the rare’ is very challenging as it can make everyday activities such as showering, bathing or even stepping outside during a rain very uncomfortable.
There is much to be learned about this allergy and much more research is needed before either the causes or the treatments are identified. While some scientists assumed that elevated histamine levels play a role in the onset of water allergy, low responsiveness to antihistamine treatment seems to contradict that theory.
Polymorphic light eruption (PLE)
Polymorphic light eruption, commonly known as sunlight allergy manifests as a rash of various forms (large or small spots, patches of varying sizes or even blisters in most severe cases) that occurs following exposure to sunlight. PLE is most commonly active during the spring and summer months and can even occur with a significant delay following exposure.
As bizarre as this might sound, PLE is actually rather common, with as much as 10% of people in the UK experiencing some form of sunlight allergy – however, keep in mind that the reactions can be very mild and thus easy to miss or misdiagnose.
Those who might suspect they are affected by PLE should see their doctor and ask about arranging for a phototesting. Phototesting relies on different wavelengths of UVA and UVB light in order to rule out other potential conditions.
Sweat allergy (Cholinergic urticarial)
Sweat allergy is another rare form of allergies that can produce a flare up manifested through changes on the surface of the skin in form of rash, hives or urticarial. Most commonly, cholinergic urticarial (CU) will manifest when the body’s overall temperature is elevated, for example, during work out session or stressful situations, but also sometimes during a hot shower or entering a hot environment such as sauna or kitchen.
Milder cases of CU are fairly common and can be easily missed, but more severe reactions are considered to be rare.
The main cause of CU is the immune system response due to increased skin temperature. As such, this form of allergy is rather specific since it is not caused by an external allergen or irritant, but the change of the property of the body. As such, CU can be managed by avoiding exposure to situations which can quickly increase the temperature of the skin.
Deodorant allergy (Axillary dermatitis)
Allergic reactions to cosmetic product are very common, with as much as 23% of women in the UK reporting some kind of skin reaction of varying intensity. But, on the other hand, an allergic reaction to deodorants and antiperspirants applied to the underarm area is much rarer. However, those affected are very likely to exhibit reactions to other cosmetic products as well.
Fish odour allergy
An allergy to seafood is nothing new or uncommon – in fact, it is estimated that as much as one in every two hundred people in the world is allergic to seafood. However, out of this number, only 15% will actually experience a reaction caused by the odour alone. However, an allergy to smell would be more than unusual, so it is important to note that this response will only occur when the seafood is being cooked and the vapours and steams are present.
When cooked, fish and seafood release a type of protein called amines which can in turn cause an allergic reaction if inhaled or contacted in some other way.
An allergy to vibrations
A very rare form of physical urticarial is caused by vibrations that seem to trigger the release of inflammatory substances into the body, thus causing hives and rashes. This type of allergy can make everyday basic activities such as clapping, running, travelling or using a drill stressful and problematic. Luckily, most reactions caused by vibrations are relatively short-lasting, usually less than an hour.
