What’s the Cushing’s threshold?

The Cushing’s threshold is understood to be the maximum dose of cortisone preparations that can still be taken daily without the risk of developing a so-called Cushing’s syndrome. If high-dose therapy with cortisone preparations is continued over a longer period of time, there is a risk that the oversupply of cortisol will lead to the so-called Cushing’s syndrome, which can be accompanied by numerous symptoms. These include among others: In order to avoid the development of such a Cushing’s syndrome, a certain cortisone dose per day should not be exceeded during long-term therapy with cortisone preparations.

This dose is different for each preparation. Moreover, it is only a rough guide. Inhaled use of cortisone, as is usually done in bronchial asthma, is less likely to lead to the development of iatrogenic Cushing’s syndrome than permanent oral or intravenous use of cortisone. For this reason, and because of the rather low dose of inhaled cortisone used in bronchial asthma, the Cushing’s threshold plays only a minor role in asthma therapy. – Redistribution of body fat with trunk obesity, bull neck and full moon face

Growth reduction (in childhood)
Increased risk of developing diabetes mellitus and high blood pressure
Skin symptoms such as thinning of the skin, red stripes of the skin (Striae distensae) and acne
Disorders of sexual function and hormone balance with cycle disorders or absence of menstruation in women
Muscular weakness
Osteoporosis with increased risk of bone fractures
Suppressing the immune system with increased susceptibility to infection
Depressions

Inhalation systems

In metered dose inhalers, the active ingredient is present in dissolved form in a pressure-resistant aluminium cartridge. The solvent used is a CFC-free propellant gas. Propellant gases can be liquefied under pressure so that the active ingredient (cortisone) can dissolve.

In some preparations, a further liquid is added to the liquid propellant gas phase. A defined quantity of active ingredient is sprayed out when a spray burst is triggered. The propellant gas evaporates abruptly and the active ingredient is released as fine droplets and absorbed by inhalation.

There are various manufacturers with different cortisone combinations. The Symbicort metered dose inhaler contains cortisone, for example. Nebulisers are electronically operated inhalation systems. In nebulizers the active substance is present as a solution which is released as very fine droplets/mist when the device is actuated. The release is relatively slow in comparison to the drug forms described above, so that more time can be allowed for inhalation.

How often should inhalers be used?

Glucocorticoids are not drugs for acute seizures, but are intended for long-term therapy! For a lasting success of the therapy it is therefore important to use the prescribed preparation regularly – even if there are no symptoms. Depending on the severity of the disease, inhalation is carried out 1 – 2 times a day.

The entire daily dose can also be taken at once. Whether in the morning or in the evening is optional. At the beginning of the cortisone therapy your doctor will prescribe higher dosages.

As soon as the effect begins and the symptoms subside, your doctor will reduce the dose. It should be low enough to ensure that your symptoms can be well controlled. It may help if you keep an asthma diary in which you record your current state of health and the dosage applied. Your doctor can then work with you to find the optimum dosage.