NOTES ON TESTOSTERONE-notes
- The body produces about 5 mg/day of TTT and 1/10 mg of DHT (dihydrotestosterone). About 2% of TTT is free, not bound.
- TTT increases muscle mass and sex drive.
- DHT increases sexual characteristics.
- TTT reduces total cholesterol, improves bone density, possible lowers HDL (good cholesterol),
and is not a causal factor in prostate cancer.
- Normal range of TTT is 306-1081 ng/dL. However,
the lower range is for 70 year olds, the range for 30-35 is 700-900 ng/dL.
- DHT binds at active sights about 10x better than TTT.
- In many target tissues TTT is reduced to DHT (G & G).
- The over-the-counter preparations (androanhdrostenedione, androstane, androsterone,
bind so weakly at sites as to be ineffective. Any medicinal quality is thus derived
from its metabolism to TTT (Goodman & Gilman 7th ed.).
- Three types of modification of TTT are clinically useful: (A). esterification to 17 β-hydroxyl group with any of
several carboxylic acids to make it lipid soluble, and of these methyltestosterone
and fluoxymesterone allow effective oral administration; (b) additions; (B) alkylation of the 17α position (as in methyltestosterone
and fluoxymesterone) allow effective oral administration because they are slowly catabolized by the liver; (C) other effective
alterations include 19-nortestosterone, cypionate and enenathate esters.
half life in blood is 10 to 20 minutes.
- Concentration in women is 15/65 ng/dL,
and daily production of 25 mg; the testes produce 20 times as much.
- Oral testosterone and nadrogens such
as as fluoxynesterone, methyltestosterone, oxandrolone, or danzaol are available for clinical use, but are not appropriate
for long-germ testosterone replacement therapy because they increase blockage of liver, enzyme drainage pathway, direct liver
damage, and even liver tumors. They also dramatically raise serum LDL, decrease
HDL. Testosterone undecanoate is a testosterone compound that is taken
up by the lymph ducts in the intestines and is able to bypass the over, thus minimizing the typical side effects, but has
a very short half life, and is currently not approved by the FDA.
- Men do not convert DHEA to meaningful levels of TTT, though women do—and it
is orally active.
to inject HCG to prevent testicular atrophy when taking testosterone--included. Testosterone
(13,700 mg) for one year of cream is $1,450 including blood test--two 6-month supplies.
(Look up testosterone on internet). HCG is a synthetic form of LH, the
pitutatary hormone that stimulates testicular TTT. It has been used as an alternative
to TTT; however, its effectiveness in stimulating TTT production is very variable—not working in a far sample of men.
- Claimed that Androstenedione is ineffective
and that FDA might remove it from shelf. Side effects decreased in HDL, acne,
shrinking of testicles, and enlargement of breasts.
Institute of Medicine in reviewing the current evidence questioned the effectiveness of long-term TTT therapy for men with
age normal TTT levels, and wants to see long-term studies of physical and psychological effects.
Chapter 59, Goodman & Gilman, 9th ed.
Senescence: As men age, the serum testosterone concentration gradually decline and the sex hormone-binding
globulin concentration gradually increases, so that by the age of 80 the total testosterone concentration is approximately
85% and the free testosterone is approximately 40% of those age 20. This
reduction in serum TTT contributes to decreases in energy, libido, and muscle mass.
These conclusions are supported by changes in younger men with hypogonadism.
In women the
loss of androgen secretion causes a decrease in sexual hair, but not for many years.
Testosterone replacement in androgen-deficient women will improve their libido, energy, muscle mass and strength, and
bone mineral density.
levels of serum TTT is 500 to 700 ng/dl in men, 30 to 50 in women. Based on this
100 mg of the TTT gel produces a level averaging 800 mg for all 24 hours in hypogonadal men, while the 10 mg patch after 12
hours falls below 600 mg, and is at 500 at the end of 24 hours. When the TTT
gel is used, there is no appreciable fluctuation during the course of the day, but steady-state values may not be reached
for a month after the initiation of treatment. Normalization of the serum TTT
concentration results in normal virilization in men who are not normally virilized and maintence of virilization in those
who are. Libido and energy in hypogonadal men should increase within a few weeks. Moreover, there are no side effects as long as the dose is not excessive.