Testolactone Chemical formula
Synonyms: 1-Dehydrotestololactone; NSC-23759; SQ-9538; Testolactona; Testolactonum; Testolakton; Testolaktoni. drosta-1,4-diene-3,17-dione.
Cyrillic synonym: Тестолактон.

💊 Chemical information

Chemical formula: C19H24O3 = 300.4.
CAS — 968-93-4.


In US.

USP 31

(Testolactone). A white to off-white, practically odourless, crystalline powder. Soluble 1 in 4050 of water; soluble in alcohol and in chloroform; slightly soluble in benzyl alcohol; insoluble in ether and in petroleum spirit. Store in airtight containers.

💊 Profile

Testolactone is a derivative of testosterone. It is reported to be an aromatase inhibitor that reduces peripheral oestrogen synthesis but has no significant androgenic activity. It has been used in the palliative treatment of advanced breast cancer in postmenopausal women. The usual oral dose is 250 mg four times daily. It should not be given to men with breast cancer. Peripheral neuropathies have occurred in patients given testolactone; gastrointestinal disturbances, pain or oedema of the extremities, hypertension, malaise, maculopapular erythema, and glossitis have also been reported.

Congenital adrenal hyperplasia.

For mention of the use of testolactone with flutamide to block androgenic effects in congenital adrenal hyperplasia.

Precocious puberty.

Encouraging results have been reported using testolactone in the treatment of 5 girls with precocious puberty due to the McCune-Albright syndrome.1 Testolactone is an aromatase inhibitor and blocks the synthesis of oestrogens from androgens. Long-term therapy (for up to 5 years) was associated with continued benefit in many patients; however, signs of puberty were not always completely suppressed, in some cases perhaps because of difficulties in maintaining the dosage regimen.2 Encouraging results were also obtained using testolactone with spironolactone in the treatment of familial precocious puberty in boys, although neither agent was successful when used alone.3 Again, signs of a reduced response to longerterm therapy have occurred; in this case control was restored by addition of a gonadorelin analogue.4 Another study5 in 10 boys who were treated for at least 6 years with spironolactone and testolactone, with deslorelin added at the onset of secondary central precocious puberty, found normalisation in growth rate and bone maturation, and improvements in predicted adult height.
1. Feuillan PP, et al. Treatment of precocious puberty in the McCune-Albright syndrome with the aromatase inhibitor testolactone. N Engl J Med 1986; 315: 1115–19
2. Feuillan PP, et al. Long term testolactone therapy for precocious puberty in girls with the McCune-Albright syndrome. J Clin Endocrinol Metab 1993; 77: 647–51
3. Laue L, et al. Treatment of familial male precocious puberty with spironolactone and testolactone. N Engl J Med 1989; 320: 496–502
4. Laue L, et al. Treatment of familial male precocious puberty with spironolactone, testolactone, and deslorelin. J Clin Endocrinol Metab 1993; 76: 151–5
5. Leschek EW, et al. Six-year results of spironolactone and testolactone treatment of familial male-limited precocious puberty with addition of deslorelin after central puberty onset. J Clin Endocrinol Metab 1999; 84: 175–8.

💊 Preparations

USP 31: Testolactone Tablets.

Proprietary Preparations

Chile: Te s l a c † ; Ger.: Fludestrin†; USA: Te s lac †.
Published March 09, 2019.