Clinical Management of Hormone Therapy

Intramuscular Testosterone

1. Most common form is testosterone cypionate followed by enanthate – esterified testosterone

2. Both have a  half life of 10 to 14 days – molecular weight of ester determines rate of absorption

3. Cypionate is less expensive than enanthate

4. Testosterone propionate has a short half life – 2 to 3 days, too short for use

5.Intramuscular injections produce reliable blood levels and can be titrated easily – ester group hydrolyzed when absorbed into bloodstream. Half life of free testosterone 10 to 100 minutes.

6. Peaks and valleys in blood levels will be seen – if too severe, a bi-weekly dosing regime can be used.  Typical starting dose in most male is 100 mgs (0.5 cc’s) per week. If dosing above 100 mgs/wk, then split dose and inject bi-weekly.

7. Injectable testosterone can stimulate bone marrow production of Red Blood Cells by enhancing production of Erythropoetic Stimulating Factor

8. In 5 to 7 percent of patients, this increase production is enough to cause  Erythrocytosis

9. Phlebotomy will be necessary to reduce the Hematocrit.

10. The Red Cross will not accept donations once the patient has  erythrocytosis, or if they are on a 5 alpha reductase inhibitor

11. Testosterone Cypionate is suspended in cottonseed oil / enanthate in sesame oil – they have different preservatives

12. Draw up with 18g 1 ½ in needle-inject with 25g  1 in needle

13. Injections are usually in upper outer quadrant of the gluteal or vastus lateralis muscle.
14. Look for trends when following up testosterone therapy –

There is a fair amount of variability in levels from day to day –

The MD should not change the dose too quickly

15. When testing BLOOD – “blood draw” is ideally done between 7:00AM  and 10:00AM