Several anabolic steroids are sold over-the-counter (OTC) in the United
States, and their production is not regulated by the US Food and Drug Administration.
Reports have suggested that use of these supplements can cause positive urine
test results for metabolites of the prohibited steroid nandrolone.
To assess the content and purity of OTC androstenedione and to determine
if androstenedione and 19-norandrostenedione administration causes positive
urine test results for 19-norandrosterone, a nandrolone metabolite.
Randomized controlled trial of androstenedione, open-label trial of
19-norandrostenedione, and mass spectrometry of androstenedione preparations,
conducted between October 1998 and April 2000.
Outpatient facility of a university hospital.
A total of 41 healthy men aged 20 to 44 years.
Participants were randomly assigned to receive oral androstenedione,
100 mg/d (n = 13) or 300 mg/d (n = 11) for 7 days, or no androstenedione (n
= 13); in addition, 4 patients received 10 µg of 19-norandrostenedione.
Main Outcome Measures
Content of OTC androstenedione preparations; level of 19-norandrosterone
in urine samples, determined by mass spectrometry, compared among the 3 randomized
groups at day 1 and day 7, and among the participants who received 19-norandrostenedione
from October 1998 to April 2000.
All urine samples from participants treated with androstenedione contained
19-norandrosterone, while no samples from the no-androstenedione group did.
Urinary concentrations were averaged for day 1 vs day 7 measurements; mean
(SD) 19-norandrosterone concentrations in the 100-mg/d and 300-mg/d groups
were 3.8 (2.5) ng/mL and 10.2 (6.9) ng/mL, respectively (P = .006). The 19-norandrosterone content exceeded the cutoff for reporting
positive cases (>2.0 ng/mL) in 20 of 24. The androstenedione preparation used
was pure at a sensitivity of 0.1%, but at 0.001% 19-norandrostenedione was
found. For the 4 participants to whom 10 µg of 19-norandrostenedione
was administered, 19-norandrosterone was found in all urine samples. Of 7
brands of androstenedione analyzed at the 1% level, 1 contained no androstenedione,
1 contained 10 mg of testosterone, and 4 more contained 90% or less of the
amount stated on the label.
Our study suggests that trace contamination of androstenedione with
19-norandrostenedione is sufficient to cause urine test results positive for
19-norandrosterone, the standard marker for nandrolone use. Oral steroid doses
as small as 10 µg are absorbed and excreted in urine. Some brands of
androstenedione are grossly mislabeled. Careful analysis of androstenedione
preparations is recommended in all studies of its biological effects.