Steroid Side Effects

To behonest, I don’t know why skin atrophy (thinning) or striae (stretch marks) occur because of steroid use and overuse. I do know, from reading drug monographs, that these effects occur in less than 1% of study participants on even the strongest of steroids with proper usage. However, while thinned skin may regain its usual thickness some time after termination of the drugs, stretch marks may be tougher to get rid of.

This is the basis for other problems. The body produces many steroids on its own, and regulates the amount of steroids produced through the Hypothalamus-Pituitary-Adrenal (HPA) Axis. This feedback loop basically measures the amount of steroids in the body, and turns the adrenal glands’ production of steroids up or down depending on the measured level.

Topically-applied steroids get absorbed into the skin, and are also absorbed into the blood stream. If too much gets absorbed, it will “fool” the HPA Axis into thinking the body is producing too many steroids. The production of steroids will be reduced accordingly. Mostly, this leads to the problem of “rebound,” but can also cause other problems (see below).

One function of steroids in the body is to regulate the amount of inflammation in an immune response. This is why topically-applied steroids reduce psoriasis symptoms, the “extra” steroids in the skin signal the immune system to reduce or shut down the inflammatory response.

For the most part, rebound occurs because of HPA Axis Suppression (see above) and a sudden termination of steroids. Once the HPA Axis is making steroids at a lower level due to systemic absorption of topical steroids, stopping the “extra” steroids too quickly will leave the body with a large deficit in these inflammation-controlling substances. The immune system can then “run wild,” and a large flare-up of psoriasis may be possible.

So, if a person has been using large amounts of topical steroids (in the case of Class I steroids, more than seven grams a day, typically), or for a long period of time (more than two weeks for the strong ones), it is a good precaution to “wean” the body off steroids, by dropping the dosage slowly. A dermatologist will be able to suggest a schedule for doing so, depending on the length of time and strength of the drugs.

Cushing’s syndrome is characterized by muscular weakness and obesity. It is usually caused by overproduction of steroids by the body itself through “hyperactive” adrenal or pituitary glands. Overuse of topical steroids can also cause reversible manifestations of Cushing’s syndrome, simply by raising the level of steroids in the body dramatically.

The steroids normally produced by the body counteract inflammation, which is a primary immune-system response to infection. If such a response is suppressed, by adding extra steroids to the body, it should be obvious that infections may thrive since the immune system will be unable to do its job properly. Most steroids come with the warning to not use them if an infection exists.

I have been unable to discover why, exactly, overuse of steroids can lead to hyperglycemia (high blood sugar) and glucosuria (high sugar in the urine). I suspect that since the hormones and other chemicals secreted by the adrenal glands have wide-ranging effects throughout the body, that suppressing their function can lead to suppression of the creation of insulin.

This possible effect is very rare when using topical steroids, but is much more common when oral, or systemic steroids (such as Prednisone) are used.