Cushing’s threshold

Definition

The Cushing’s threshold describes the amount of glucocorticoids (e.g. cortisone) that is given in the form of a drug and by which the clinical picture of Cushing’s disease is triggered. Since it is not a true Cushing’s syndrome, it is called Cushing’s syndrome. The way this disease is triggered by a drug is also called iatrogenic (literally “triggered by the doctor”). In this disease, an excessive dose of glucocorticoids causes a typical external appearance with certain specific recognition features. These include trunk obesity, a bull’s neck and a full moon face as well as virilization, i.e. masculinization.

Threshold dose

The threshold dose for Cushing’s disease depends on many factors. One of these factors is the method of drug administration, as intravenous administration of the drug has different consequences than, for example, administration in the form of a skin ointment. Another factor is the individual response to the medication.

This means that each person reacts differently to a drug. Furthermore, the drugs also differ from one another. Cortisone, for example, has the highest Cushing’s threshold dose of about 40 mg per day in men.

Women have a slightly lower Cushing’s threshold due to different body metabolism levels. It is 25-30 mg per day before menopause, and 15-25 mg per day afterwards. This means that administration of more than 40 mg per day can trigger the clinical picture of Cushing’s disease.

In comparison, the threshold dose for prednisolone administration is only about 7.5 mg per day and is thus significantly lower than that of cortisone. The lowest threshold dose of frequently used drugs is betamethasone at 1 mg per day. In children, care must be taken to ensure that they have different threshold doses for different preparations due to different body conditions.

Unfortunately, there are also many children’s diseases for which the use of glucocorticoids as therapy is necessary. Therefore, special care must be taken to ensure that nothing triggers a Cushing’s syndrome at such an early age through an overdose of glucocorticoids. The Cushing’s threshold dose in children for the preparation prednisone is 6 mg per m2 body surface area per day. However, this amount should only be seen as a guideline for children, as the processing of the preparation in the body can vary from child to child.

What do you need the Cushing’s Threshold for?

Many different diseases are treated with the help of glucocorticoids. These are mainly chronic diseases that accompany the affected person for the rest of his life. Frequently occurring examples of this are: It is also becoming more and more common for people to suffer from several of these diseases at the same time and accordingly therapeutic glucocorticoids are used to treat various diseases on a regular basis.

It is therefore very important to ensure that the high use of glucocorticoids does not lead to an additional new and stressful clinical picture. The Cushing’s Threshold is therefore used as an aid to relieve the patient with his or her diseases instead of putting additional strain on them. Doctors can use this as a guide when prescribing glucocorticoids in order to avoid unnecessary side effects.

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  1. Cushing’s threshold
  2. What happens when the Cushing’s threshold is crossed?