Drug intolerance

introduction

Medication intolerance is an immune reaction of the body to locally applied or otherwise taken medication. So it ultimately describes a type of allergy.
As with other allergic reactions, it is an excessive reaction of the immune system to substances that are harmless in themselves (Allergens). This defense reaction is then expressed in inflammatory processes, which can take on the most varied of manifestations.

trigger

It is often the same types of medication that cause intolerance in many cases.

In principle, can all medication Be the trigger of a drug intolerance. However, at certain medicines are particularly common allergic reactions observed.
These include in particular

  • Antibiotics
  • Anti-epileptic drugs
  • X-ray contrast media
  • Painkiller (Analgesics)

This is partly due to her chemical nature, but also because these drugs prescribed more often than others and be taken. Typical triggers of an immune reaction are also gold preparations, which are still used during treatment rheumatic diseases are used. Besides these synthetically manufactured preparations you can also herbal medicines (Phytotherapeutic agents) and even Vitamin preparations Trigger intolerance.

Typical for Allergies in general are so-called Cross allergies. A chemically related substance can contribute to this intolerance another substance can also trigger an allergy. A classic example of this is the intolerance of apples to existing ones Birch pollen allergy; both contain a very similar protein. A common cross-allergy related to medication is that of Penicillins and Cephalosporins (both Antibiotics).

Symptoms

Medication intolerance can cause a wide range of symptoms, but most of them are quite harmless. The most common here are Rashes, itching, Blistering and Hives (Urticaria). Strength allergic reactions can turn out to be allergic asthma represent. This releases the secreted by immune cells histamine a swelling of the Bronchi and thus a Shortness of breath out.

In the worst case it can lead to anaphylactic shock come, the maximum reaction of an allergic reaction. Which without immediate therapy can be fatal. At the beginning, symptoms such as itch, Burn and Feeling hot in the throat and the tips of the fingers and toes.
Almost parallel to it difficulties swallowing and a Bronchospasm which can lead to shortness of breath. The resulting lack of oxygen in the body manifests itself in a Blue discoloration of the lips (cyanosis). As a result, it comes to Circulatory shock With Drop in blood pressure and Racing heart (Tachycardia).

If symptoms such as severe itching, asthma and swelling of the lips or face are observed after taking medication, you should immediately Emergency doctor to call.

skin rash

skin rash (Rash), more precisely a Drug eruption is the outward appearance of a drug intolerance and represents the most common manifestation this one.
When you first take a drug, a rash usually occurs between the 7th and 12th day of treatment on. If the drug has been taken before, one has already found one Awareness instead and drug eruptions are already occurring within the next 48 hours on.
In addition to a real allergic reaction, however, it can also be a so-called Pseudo allergy act, which without sensitization can trigger a rash after taking the drug for the first time.

The Appearance of a drug eruption can differently fail. Scarlet-like redness, a measles-like rash or small round or oval nodules (papules) can occur. It rarely happens Formation of large red spots, so-called Erythema. However, it is characteristic of all drug-related rashes that they mostly occur different, but always the same body parts individually occur. Once the rash has healed, it usually remains for the next time greyish pigmented skin back.

For more information, please also read our page Medication rash.

ASA intolerance

Between 0.5 to about 6% of all people have an intolerance to aspirin (Acetylsalicylic acid, short ASA); at Asthmatics the intolerance rate even lies between 20 - 35%. So that is ASA intolerance one of the most common drug intolerances.
Contrary to its name, however, it is not just one Intolerance to ASAbut against a large group of Painkiller, the so-called NSAIDs, to which too Ibuprofen and Diclofenac counting. Early signs of ASA intolerance are usually one Runny nose with a Odor reduction and recurring (recurrent) Nasal polyps. Come later Hives (Urticaria) and asthmatic complaints.

X-ray contrast medium intolerance

Allergic reactions to X-ray contrast media are with about 4 to 13% of all applications also quite often.
Two types of reaction play a role here. In the Immediate response complaints occur within a few minutes to an hour. These complaints usually take the form of skin rash on, but can also appear as nausea, Vomit and stomach pain represent.
In extreme cases it comes to anaphylactic shock with dangerous breath- and heart-Circulatory problems.
Late reactions however, only occur after about 7 to 24 hours as blotchy, nodular rashes and itching on. If a patient is known to be intolerant to a contrast medium, but the administration of contrast medium is unavoidable, an allergic reaction can be caused by Glucocorticosteroids, so Cortisol, or Antihistamines be prevented.

Therapy of drug intolerance

Is there any suspicion of a Drug intolerance, should always be a doctor to be visited. The most important measure in the following is that Stop taking medicationto which the allergenic effect is ascribed. Confirmed when subsequently made Testingthat this drug actually the trigger the immune reaction, care should be taken to ensure that this and chemically related drugs are no longer administered in the future.

If the allergy is more severe, you can Cortisol or Antihistamines be administered, which weaken the immune response. This means that symptoms can be eliminated quickly. Should be followed by a Allergy test be performed. It can also be helpful to issue a Allergy pass in which the allergenic substances are listed. This should always be carried with you.

How can I find out if I have a drug intolerance?

Figuring out what drug the allergic reaction triggered is often difficult, there usually several Drugs at the same time be taken. It is also possible that a skin rash instead of a drug by a virus was triggered, he should under a cold occur. To clarify possible drug intolerance, there are a number of Investigations available; however, the prick test or Blood tests carried out.

The prick test, too skin prick test (abbreviated SPT) is the most commonly used method for all allergic tests. Here, individual drops of an allergen-containing solution are applied to the patient's forearm or back and inserted about 1 mm into the skin with a fine needle. After about 15 minutes a Immediate response can be read. Besides this method exist a number of other testswhich are also used superficially on the skin.

To diagnose a drug allergy are also Blood tests a suitable means. This is the total number of an allergy-related subgroup of Antibodies, the IgE antibodies. It is also possible to look for IgE antibodies, which specifically against an allergen are directed. However, it is problematic that IgE also occurs in parasitic or some hematological diseases be increased and thus falsify the measurement results.

Tests like the skin prick test can, in spite of everything not sure about the prognosis used by drug intolerance. In some cases, severe immune reactions to drugs were observed even after negative tests.