Allergy: immunotherapy with tablets

Around seven percent of Germans are allergic to house dust mites. Studies have shown that immunotherapy with tablets instead of injections, as has been the case before, is remarkably effective

Tens of thousands of animals live in Germany's households - in every single one. You cannot play or cuddle with them, as they are only 0.2 millimeters in size on average and are therefore practically invisible to the human eye. The tiny arachnids are called Dermatophagoides. Or: dust mites.

Their presence is not a sign of poor hygiene, but quite normal. Mites feed on the flakes of skin that everyone loses. However, around seven percent of the population have an allergic reaction to arachnids - more precisely to protein components in their excretions. And there are plenty of them in every bed. There the mites feel particularly comfortable due to the temperature, the humidity and the abundant food supply.

Short-term drug effects

If the protein fragments get into the airways, allergy sufferers react with a runny nose, the throat itches, the eyes swell and water. But it often doesn't stop there. People with a dust mite allergy often develop bronchial asthma, which gets worse over time. Figures show that such a so-called change of floor from the upper to the lower respiratory tract occurs significantly more often in people who are allergic to mites than in people who are allergic to grass or pollen.

"The usual anti-allergic drugs only help against the symptoms for a short time, but do not fight the cause," says Professor Timo Buhl, allergist at the University Hospital in Göttingen. They did not prevent the change of floor or the worsening of asthma. Instead, Buhl often prescribes a corticosteroid nasal spray at the beginning: "This makes the nasal mucosa swell. But it is primarily a good strategy to show the patient how much better he could be with a good therapy."

Used to a cold

While pollen allergy sufferers notice a deterioration depending on the season, mite allergy sufferers suffer from symptoms all year round. So the cold becomes a permanent condition; the snoring caused by the narrowed airways and the increased susceptibility to infection are also accepted as normal. "Due to this habituation effect, the patient no longer notices how badly he is actually doing," says Buhl.

Despite good treatment options, only around ten percent of those allergic to mites currently benefit from adequate therapy, say doctors. Specific immunotherapy is currently the gold standard.

Tiny amounts of the triggering allergen are injected under the skin of the patient at intervals of several weeks. In this way, the immune system learns to tolerate the protein. There are now tablets and drops on the market that patients can take themselves. Because the allergen extracts are absorbed through the oral mucosa under the tongue, the procedure is called sublingual immunotherapy.

Tablet or syringe?

"This is more convenient for many patients because they don't have to see a doctor that often," says Buhl. However, the preparations usually have to be taken daily. And the sublingual agents often have local side effects, such as a tingling sensation on the tongue or a slight swelling of the lips. Which variant you choose is a matter of personal preference, says Buhl. According to the current state of knowledge, they work about equally well.

This is confirmed by Professor Johann Christian Virchow, Head of the Department of Pneumology at the University of Rostock: "The study situation on sublingual immunotherapy is getting better and better due to the larger number of cases and dose-dependent examinations."

The treatment also helps asthmatics - provided they are also allergic to house dust mites. This is borne out by the results of a study in which Virchow played a leading role. As the expert emphasizes, this immunotherapy also benefits patients whose asthma could previously only be moderately controlled. You then needed less cortisone spray.

Reward after lengthy therapy

Whether syringes, tablets or drops - in any case, successful immunotherapy takes around three years. At least. Not every patient can cope with this. "The drop-out rate is unfortunately very high, especially at the beginning," complains allergist Buhl. This is especially true for oral therapy, which is difficult to monitor. For some of those affected, the procedure may be too laborious.

"Many are also disappointed because the effect does not set in in the first few weeks," says Buhl. But those who persevere will be rewarded.Buhl estimates that around 90 percent of patients would experience significant improvement through specific immunotherapy.

Spanish scientists who evaluated 112 studies on the subject also came to a positive result. In addition: the effect lasts for many years. And even if symptoms reappear at some point, the treatment can be repeated without any problems. It is rather unusual that allergy sufferers do not respond to the therapy at all. Then, according to the expert Virchow, there is often a suspicion that the patient may not have taken the preparation.

Help against mites

  • Encasings: These covers for mattresses and duvets (including those of your partner) keep mites away from the body. Pay attention to good breathable quality.
  • Hepa filters for vacuum cleaners: They hold back most of the dust. Avoid carpets and home textiles, especially in the bedroom. If possible, do not dust and vacuum yourself.
  • Air washer: Devices that also clean and filter the room air are well suited if all other measures have already been exhausted.
immune system