Allergic contact dermatitis due to nickel

Allergic contact dermatitis due to nickel 1920 1280 Jaritzy Negrín González

Nickel is a hard, malleable and ductile metal that forms fundamentally divalent compounds, mostly nickel salts (Chloride, Sulfate, Nitrate) of bluish green color.

It is the most common cause of allergic contact dermatitis in patients undergoing patch tests.

Where do you find it?

In multiple everyday objects: jewelry, scissors, keys, doorknobs, coins, clothing buttons, belt buckles, headphones, mobile phones, among others.

Sweating and close contact with the skin facilitate absorption and can lead to symptoms.

How does allergy occur?

As we have explained in many of our contents, frequent exposure to an allergen, in this case nickel, increases the risk of sensitization and allergy.

It has been associated with the use of earrings or body piercings.

What symptoms can you have?

Common reactions are eczema-like lesions in the area of contact, red skin that itches.

Delayed reactions such as airborne reactions from the use of sprays or systemic contact dermatitis may also occur.
It can be the origin of dermatitis in professionals such as cashiers, jewelers, electricians, car mechanics, painters, among others.

What should you do?

You must go to your allergy specialist, who will assess your case, and if necessary, perform patch tests. And you will have to avoid the use of objects that contain nickel.

Any doubts?

Contact with us

Dra Jaritzy Negrín González
Allergy Specialist

Differences between alergic rhintis and cold

Differences between alergic rhintis and cold 1920 1280 Federico de la Roca Pinzón

When we have congestion, runny nose and sneezing, most of us think we are facing a cold. But what about those people who have allergic rhinitis? In them nasal congestion and sneezing are very frequent symptoms. How can a person with allergic rhinitis differentiate the symptoms of a cold from those of rhinitis? In this post we try to answer this and other questions related to allergic rhinitis and cold.

What is rhinitis?

If we look for the definition of rhinitis we will find that it is inflammation of the nasal mucosa, which is usually accompanied by nasal discharge, congestion and sneezing. As you can see, any of these symptoms can occur in the cold as in allergic rhinitis. Therefore, what at first glance seems to be a very simple distinction in non-allergic people, the differentiation is more complex in those who suffer from allergic rhinitis and catch a cold (something very common in the autumn and winter months).

What is cold?

If we also review the different types of rhinitis we find that the common cold is also a type of rhinitis, an acute infectious rhinitis. Therefore, neither the definition of rhinitis nor its classification help us to solve a very frequent question in allergology consultations: I don’t know if what I have is rhinitis or a cold?

How to differentiate cold symptoms from those of allergic rhinitis?

Despite the fact that, as we have seen, the symptoms are very similar, there are small differences that can be helpful in distinguishing a cold from allergic rhinitis:


  • Mucous/thick nasal discharge.
  • Yellow or green discharge.
  • It can associate fever and malaise.
  • Sometimes it can be accompanied by a headache.
  • Sore throat and cough with expectoration may also appear.
  • It usually requires 5 to 10 days for recovery.


  • Runny nose.
  • White or clear discharge.
  • It is NOT associated with fever or malaise.
  • Sometimes it can be accompanied by itchy nose and eyes.
  • Sometimes there is itchy throat or a feeling of mucus in the throat
  • Symptoms may subside in less than 24 hours.

And if you can’t tell a cold from allergic rhinitis, what can I do?

If, despite the differences listed above, it is not  possible to  distinguish whether it is an allergic rhinitis or a cold, can I take my allergy medication, even if it is a cold? The answer is yes. Anti-allergic medication, nasal corticosteroids and oral antihistamines, can be taken in case of a cold. In fact, many flu medicines contain antihistamines, although usually in the middle of the usual dose. In addition, if we remember, the cold is a type of rhinitis, so inflammation of the nasal mucosa, even if it is of infectious origin, can be treated with nasal corticosteroids.

The problem could occur in the continued use of oral antihistamines in the case of a cold instead of allergic rhinitis. A good time to stop taking antihistamines is the presence of thick, yellow or green nasal secretions. These secretions respond better to nasal washes or mucolytic than to antihistamines.

What precautions can I take not to catch a cold?

There is no specific precaution to avoid colds. But as it is an infection of viral origin, it is recommended:

  • Frequent hand washing with soap and water for at least 20 seconds. If soap and water are not available, hydroalcoholic gel can be used if it contains at least 60% alcohol.
  • Avoid touching your face, eyes, nose or mouth with dirty hands.
  • Frequently clean and disinfect frequently touched surfaces (mobile devices, keyboards, doorknobs, etc.).
  • Avoid close contact with anyone who has symptoms suggestive of a cold.
  • If you have a cold or think you have a cold, cover your mouth when you sneeze or cough. Use tissues and throw them away immediately after use. Whenever you have contact with secretions you should wash your hands.
  • Currently the use of masks is increasingly common. Surgical masks can prevent transmission from a cold person. If you have a cold you can use this type of mask and you will protect those around you.

If I am allergic and catching a cold, what precautions should I take?

Cold symptoms in allergic people can be more intense and if not controlled can be complicated by sinusitis or trigger bronchial symptoms such as shortness of breath, choking sensation or wheezing. The recommendations to avoid these complications are:

  • If nasal congestion is important, intense nasal washes can be performed morning and night.
  • Make use of nasal corticosteroids according to the usual guideline prescribed by your allergology specialist.
  • Avoid taking oral antihistamines.
  • If you are asthmatic, you should monitor for any exacerbation of asthma. If you have bronchial symptoms you should return to your usual inhaler and perform it according to the guideline prescribed by your allergology specialist. If you are already being treated with an inhaler you can double the dose until it is evaluated by a physician.
  • If the nasal symptoms last for more than 10 days, associate high fever or difficulty breathing despite the use of a bronchial inhaler you should go to a medical evaluation.

At ClinicAL we hope to have responded to a very common situation in these cold months where colds are very frequent and their complications can be very important in patients with allergic rhinitis.

¿Tienes alguna duda?

Contacta con nosotros y te ayudaremos a resolverla.

Dr Federico de la Roca Pinzón
Especialista en Alergología.


SHELLFISH ALLERGY 1920 1147 Jaritzy Negrín González

What is shellfish?

They are aquatic invertebrate animals, edible. They include crustaceans with more than 50,000 species such as shrimp, lobster, lobster, prawn… and molluscs made up of more than 100,000 species of bivalves (clam, mussel, oyster), cephalopods (octopus, cuttlefish, squid) and gastropods (snail, limpets). Not necessarily if you have an allergy to one of them, you have to have them all.

Shellfish are one of the most frequent causes of food allergy, its prevalence is linked to the frequency of its consumption.

Can you get a “shellfish allergy”?

The answer is YES. It is a hypersensitivity reaction with an immune mechanism, usually mediated by an antibody called IgE, which develops after ingestion, contact or inhalation of vapours from these foods.

Shellfish allergy is also considered an occupational disease that is, people who work in a food industry, due to the frequent handling of these foods, they can develop allergy.

Who is responsible?

Shelfish proteins are the allergens that cause allergy. Among these proteins we have Tropomyosin. It is a contractile protein, that is, it intervenes in the contraction of the muscle cells of all species of invertebrates. Allergenic tropomyosins have been described in numerous invertebrate species: crustaceans, molluscs, arachnids (dust mites) and cockroaches.

If you have a shellfish allergy, you may become allergic to dust mites or vice versa. But it is not necessarily a condition to have both allergies Remember that immune, genetic, and exposure factors are involved for an allergy to occur.

Other causative allergens are: arginin kinase,myosin light chain, calcium-fixing protein, hemocyanin,  paramyosin.

What symptoms can you have?

The most frequent allergic reactions to shellfish are those mediated by IgE, usually occurring whitin the first hour of exposure to the food. The most frequent symptoms are on the skin (hives, itching, erythema, angioedema); digestive, respiratory or all symptoms can also occur, which is what we call anaphylaxis.

What should you do if you’ve had suspicious symptoms of shellfish allergy?

You should go to an allergist. Initially, a detailed medical history of what has happened will be made and according to its assessment it will determine to carry out allergy tests: prick test and a blood test if necessary. It is also possible that an oral provocation test will need to be performed and the study of other shellfish other than the one involved should be evaluated to rule out or diagnose cross-reactivity which may happen because shellfish share homologous allergenic proteins.

If you are already diagnosed with shellfish allergy, what should you do?

You should avoid exposure to shellfish and if you have an accidental exposure follow the instructions of your allergist.

It usually consists of medication with antihistamine, corticosteroids and / or adrenaline as the case may be.

Dra Jaritzy Negrín González.
Allergi specialist.