Severe doubts subsist about the reversibility of the contraception produced by
gossypol (possible permanent damage to the testes) and the hypokaliemia
observed in some subjects.

see: Woolley-RJ  J-Am-Board-Fam-Pract. 1991 Mar-Apr; 4(2): 103-13

      Zhong-CQ; Lui-QL; Tang-YJ; Wang-Y; Shi-FJ; Qian-SZ
     Contraception. 1990 Jun; 41(6): 617-22

Big doubts subsist with regard to two significant adverse effects of gossypol:

1- the hypokaliemia observed in a small group of subjets taking it, and

2- the reversibility of the contraception.

see:  Woolley-RJ in  J-Am-Board-Fam-Pract. 1991 Mar-Apr; 4(2): 103-13.

 Zhong-CQ; Lui-QL; Tang-YJ; Wang-Y; Shi-FJ; Qian-SZ
SO: Contraception. 1990 Jun; 41(6): 617-22
AB: Sperm function was assessed in 19 men 3-10 years after cessation of gossypol
treatment and 2-9 years after recovery of normal sperm density. Nineteen normal
fertile men of similar age served as the controls. The results showed that sperm
function in the treated group was lower than that in the control, which may be a
result of persistent gossypol-mediated damage to the testes.

"Animal studies were completed in 1971, and these provided definitive proof of
the efficacy and safety of the major constituent, gossypol. Clinical trials began
in 1972 with men receiving a daily dose of 20 mg until their sperm counts dropped
below an acceptable level. They then took a maintenance dose of 75-100 mg twice a
month. Among the first 4000 men treated over periods ranging from 6 months to 4
years, the estimated efficacy of this regimen was 99.9 % and there was complete
recovery of acceptable sperm counts 3 months after the last dose of gossypol.
Only time will tell whether this form of contraception is safe, effective and
acceptable to western men"

What is the answer to his last sentence?
—————————————————————————–
Dennis Jarvis,          CSIRO Division of Manufacturing Technology,
                        PO Box 4, Woodville, South Australia 5011, Australia.
PHONE: +61 8 268 0156   Internet  : d…@adl.dmt.csiro.au
FAX  : +61 8 268 6757   UUCP  : uunet!adl.dmt.csiro.au!dhj
TELEX: AA88863          ACSnet: d…@aegir.dmt.oz

Pat Leary <p…@cornell.edu> wrote:
>Can anyone enlighten me as to how "thyroid extract" can be sold without a
>prescription? Is it because it’s ineffective?

It was common to prescribe "dessicated thyroid" (of either bovine
or porcine origin–can’t remember) as thyroid replacement therapy
before l-thyroxine in its pure form became widely available.
This was a fairly standardized and uniform product, and it is still
available for sale with a doctor’s prescription.  If you see "thyroid
extract" for sale in health food stores or from hucksters, it’s
nothing more than snake oil designed to catch the eye of people
who hope they need thyroid replacement.  I would be very surprised
if it had any measurable amount of thyroid hormone in it.  The FDA
would be surprised, too.

–
Steve Dyer
d…@ursa-major.spdcc.com