Prednisone and HPA Suppression
A potential side effect of glucocorticoid therapy is adrenal suppression, or what is more accurately called HPA (interaction between the hypothalamus, pituitary and adrenal glands) suppression. Anyone on prednisone, or a similar steroid in a dosage over 5 mgs.(prednisone) has to be alert to the possibility of this side effect. It used to be thought by some that daily doses under 7.5 did not result in HPA suppression, since most people pump out about 7 mg of cortisol daily on their own. However, this judgment about a 7.5 threshold no longer prevails.
There are several ways to try to protect against HPA suppression. The most well-known is to dose down very slowly from a high dose to a low dose. In that way, the body can start compensating for the gradual decrease in serum glucocorticoid levels. There is really no set schedule for how this dosing down–or weaning–is done. The process can be influenced by the age of the patient and by other factors, such as kidney and liver function. A doctor has to evaluate the progress of each patient who is weaning down from high-dose steroid therapy and adjust dosing accordingly.
One thing I learned from reading about prednisone and HPA suppression was that the way a dose is administered increases or decreases the likelihood that HPA suppression will occur. Alternate day dosing, if possible, seems to result in a reduced risk of HPA suppression. Also, taking one dose in the morning, instead of a split dose (morning/late afternoon or evening) also seems to result in less HPA suppression. Cycling regimens, if possible, in 5 day on and two week off segments also reduces the likelihood of HPA suppression. However, if the cycle is two weeks on and two weeks off, then HPA suppression is more likely.
What was surprising to me about this information was that it is not necessarily the total dose of steroid taken which resulted in HPA suppression. The way in which the dose is administered is also important.
Personally, I will change my habits. When I’m trying to wean off prednisone, I have noticed that taking a little booster dose at night, as little as .5 mg, increases my chances of sleeping through the night comfortably. I will not do this any more. Even if it means I’ll have to take the extra .5mg in the morning, I will go that route. Or I will just put up with less sleep.
The original link I posted for information about HPA suppression and prednisone doesn’t work so I have found another source that seems responsible. The following link is to an article published by the University of California and is meant to inform healthcare professionals about the possiblity of HPA suppression in patients who are facing surgery.