The references I provided are not restricted to orally administered
corticosteroids.

The reference you provide is from an organization sponsored by sellers of
hydrocortisone and other "skincare products"...

Even if it were true that one needs those large amounts of hydrocortisone to
achieve Adrenal Gland SUPPRESSION, and Cushing's Syndrome, I'm not talking
about reaching that level of toxicity. My concern is that the treatment of
HCV infection is of limited efficacy as it is. Anything that may hamper the
full efficacy of the treatment should be avoided, and anything one can do to
optimize the benefit of the treatment should be adopted if tolerable.
I agree with you that "in many cases, ... safer alternatives are
insufficient and have to be supplemented with appropriate medication,
including OTC and prescription strength corticosteroids." Furthermore, some
people have to stop treatment altogether due to side effects. But, as a
general rule, I wouldn't use OTC hydrocortisone cream or any other
corticosteroids (unless it is on a very small portion of the skin) because
they suppress the immune system, even if it were a small effect, during
treatment.

The following references supports my suspicions about using hydrocortisone
during treatment :

West J Med. 1995 February; 162(2): 123-126.
Adverse effects of topical corticosteroid use.

D A Fisher
Department of Medicine, University of California, School of Medicine, San
Francisco, USA.

Topical corticosteroid use, a common and often efficacious therapy for a
wide variety of cutaneous conditions, may have substantial adverse effects.
These range from the notable nondermatologic side effects of
hypothalamic-pituitary-adrenal axis suppression, Cushing's disease, femoral
head osteonecrosis, and cataracts to a variety of less serious skin effects
such as cutaneous tinea and contact dermatitis. The broad availability,
efficacy, relative low cost, and ease of applying topical corticosteroids
should not induce complacency or a cavalier attitude in prescribers.
Physicians should have the same awareness of the possible side effects of
topical steroid use as when prescribing parenteral medication.
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Br J Dermatol. 1986 Oct;115(4):475-84.
Effect of percutaneous absorption of hydrocortisone on adrenocortical
responsiveness in infants with severe skin disease.
Turpeinen M, Salo OP,  Leisti S.

Percutaneous absorption of hydrocortisone was studied in 18 children (aged
from 6 weeks to 14 1/2 years) with atopic or seborrhoeic dermatitis, by
measuring their serum cortisol before and after application of 1%
hydrocortisone cream. Endogenous secretion of cortisol was suppressed with
dexamethasone. A 24 h absorption test was performed on nine children. In
six, percutaneous absorption was detected. The highest serum cortisol level
was reached within the first 6 h. A 4 h absorption test was developed on the
basis of the 24 h test. This short absorption test was performed on nine
children, and in eight of them absorption of hydrocortisone was detected.
The rise of serum cortisol ranged from 98 to 2669 nmol/l. The 2 h ACTH test
was performed to evaluate the effect of previous treatment with topical
glucocorticoids. Suppressed adrenocortical function was found in five of 13
children, and was associated significantly with high post-application serum
cortisol levels. This occurred more often in infants with a severe skin
disorder than in older children or in those with mild or moderate skin
disease.
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Useful references that highlight some concerns in this context:
http://health.yahoo.com/drug/d03205a1
http://www.pubmedcentral.nih.gov/picrender.fcgi?artid=1417221&blobtype=pdf

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