Sunlight

Some people are so sensitive to the ultraviolet light of the sun that they experience something called a polymorphic light eruption (PLE). This can result in a rash, sometimes after just a few minutes outdoors. The condition is very common and not usually dangerous, but it can be itchy and uncomfortable. It usually goes away within a few hours. Sunscreen of at least SPF 30 can help. You can also be treated with oral antihistamines or topical steroid cream. If you’re severely affected, you may want to try desensitisation therapy. This involves being gradually exposed to more and more UV light from the spring onwards, so that the body can acclimatise and build up its natural protection.

Loose change

Allergic to money? You may be. 10% of people in the UK are thought to be allergic to nickel. So, the decision by the Royal Mint to coat 5p and 10p coins with nickel instead of a copper-nickel alloy, has raised concerns over allergic skin reactions. Nickel is found in coins, jewellery, keys and other everyday objects. It’s also one of the leading causes of allergic dermatitis, which can leave you with a nasty, itchy rash. Bank clerks and cashiers may have a higher risk of an allergic reaction. Allergy UK warns men who carry coins in their pockets can develop sore, itchy skin on their thighs. However, if a bad penny is rubbing you up the wrong way, it’s not a major health crisis. You can easily be treated with corticosteroid cream.

Skin graffiti

Dermatographia is a rare skin condition, also known as 'skin writing'. Even the lightest touch to the skin can result in raised red welts minutes later. The welts usually disappear in about 30 minutes but can be made worse by anxiety and warm temperatures. The condition affects about 5% of the UK population and can be triggered by clapping hands, rubs from clothes or bed sheets and even just sitting. Antihistamines are often prescribed to ease the symptoms.

Sweat

Being hypersensitive to sweat is actually fairly common. It’s called cholinergic urticaria, or simply, heat bumps. The rash is very distinctive, forming tiny weals with a red flare around each one. The rash appears within minutes of working up a sweat and is worst on the arms, chest and back. You may get wheezy or short of breath, too. Rashes can also be triggered by hot showers or baths. They usually go away after about 30 minutes.

Exercise

It's no fun when a trip to the gym can trigger a rash and vomiting caused by exercise-induced anaphylaxis. This condition is rare and occurs after exercising. It can be serious and even fatal, if your heart stops pumping properly. Jogging is the most common cause, but even low-impact activity like gardening can trigger it. In some cases, there can be symptoms after exercising, or due to eating certain foods before exercising. This is a complex condition, so you’ll need to be referred to an NHS allergy clinic where a specialist can assess if you need to be prescribed an adrenaline injection.

Sex

It should be a joy but for some allergy sufferers, sex can be a pain. Some women have been known to be allergic to their partner's semen. Symptoms usually appear within an hour of sex and range from itching and inflammation, to pain going to the loo and even anaphylactic shock. If you’re worried, seek medical advice. There are ways to protect yourself, such as gradual exposure to sperm to build up tolerance, and condoms.

Your period

The 'time of the month' is linked with a condition known as autoimmune progesterone dermatitis (APD) for some women. This happens when a woman is allergic to her own progesterone. It can trigger mouth sores, or a body rash, usually 3 - 10 days before the start of a period. Reactions may be triggered by taking contraceptive pills, or other products containing progesterone, that result in sensitisation to the woman’s own progesterone hormone. Mild cases can be treated with antihistamines, corticosteroid skin creams or hormone therapy. Rarely, a woman may need removal of her ovaries.

The cold

Some people are hypersensitive to the cold. This rare condition is known as cold urticaria and most often affects younger people. Reactions range from red, itchy welts to low blood pressure, shock, loss of consciousness and even death. It’s most commonly triggered by swimming in cold water. You may also notice your hand swelling after holding cold objects, or swollen lips or tongue after consuming cold food or drink. Seek medical advice if you think you are abnormally sensitive to cold temperatures. It usually goes away on its own over time, but it can be treated with antihistamines.

Related reading

• 9 hidden allergy hotspots in your home
• Life-threatening allergy triggers
• Myths and facts about seasonal allergies
• Pet allergies slideshow
• 10 common allergy triggers
• Slideshow: Food allergy triggers