During conventional pharmacologic dose corticosteroid therapy, ACTH production is inhibited with subsequent suppression of cortisol production by the adrenal cortex. Recovery time for normal HPA activity is variable depending upon the dose and duration of treatment. During this time the patient is vulnerable to any stressful situation. Although it has been shown that there is considerably less adrenal suppression following a single morning dose of prednisolone (10 mg) as opposed to a quarter of that dose administered every six hours, there is evidence that some suppressive effect on adrenal activity may be carried over into the following day when pharmacologic doses are used. Further, it has been shown that a single dose of certain corticosteroids will produce adrenal cortical suppression for two or more days. Other corticoids, including methylprednisolone, hydrocortisone, prednisone, and prednisolone, are considered to be short acting (producing adrenal cortical suppression for 1¼ to 1½ days following a single dose) and thus are recommended for alternate day therapy.
Also, when given in very large doses (many puffs from a high-concentration steroid inhaler), the amount of steroid medicine that spills over into the bloodstream can become significant. Although the effect is small, like a very small dose of prednisone, over the years this small effect can potentially add up to serious harmful effects. High doses of inhaled steroids taken for a long time can probably predispose to cataracts, glaucoma, and thinning of the skin and bones. As a result, your doctor will probably only have you take high doses of inhaled steroids as a means to avoid steroid tablets. And he/she will constantly work with you to attempt to reduce the dose of inhaled steroids to a more conventional and safer range.
Your doctor may suggest it is worth using a loaned/hired nebuliser for several weeks to see if it is of benefit to you. In each area hire/loan pools are operated by different agencies. Your doctor or the local Asthma Society will know where you can find one near you.
Only a doctor can prescribe the nebuliser medication and give approval for you to hire a nebuliser. Specialists at the hospital may arrange for some of their patients to have a nebuliser on loan from the hospital. You may be asked to keep taking peak flow recordings during your nebuliser trial.
Often an inhaler with a spacer is as effective for most people, provided adequate doses of medication are given. Because a nebuliser is a machine and costs a lot more money than an inhaler and spacer, it does not necessarily mean it is the best choice for you.