Mechanism of effect
Fluoxymesterone is a synthetic androgenic anabolic steroid and is approximately 5 times as potent as natural methyltestosterone. Like testosterone and other androgenic hormones, fluoxymesterone binds to the androgen receptor. It produces retention of nitrogen, sodium, potassium, and phosphorus; increases protein anabolism; decreases amino acid catabolism and decreased urinary excretion of calcium. The antitumour activity of fluoxymesterone appears related to reduction or competitive inhibition of prolactin receptors or estrogen receptors or production.
Pharmacodynamic
Fluoxymesterone is a synthetic androgen, or male hormone, similar to testosterone. Fluoxymesterone works by attaching itself to androgen receptors; this causes it to interact with the parts of the cell involved in the making of proteins. It may cause an increase in the synthesis of some proteins or a decrease in the synthesis of others.
These proteins have a variety of effects, including blocking the growth of some types of breast cancer cells, stimulating cells that cause male sexual characteristics, and stimulating the production of red blood cells.
Pharmacokinetics
- Half-Life: 9.2 hr, longer t1/2 than natural androgens
- Bioavailability: PO: rapidly absorbed
- Protein Bound: 98%
- Metabolism: liver
- Excretion: urine (90%)
Dosage
- Adult
Hypogonadism, Males
5-20 mg PO qD
Metastatic Breast Cancer, Females
Palliative adjunctive therapy: 10-40 mg/day PO in divided doses x3 months or longer
- Pediatric
Delayed Puberty, Males
2.5-20 mg PO qD x4-6 months
Hypogonadism, Males
As adults; 5-20 mg PO qD
Alerts
caution
Benign prostatic hypertrophy, males with delayed puberty, geriatric pts, pediatric pts
Hypercalcemia may occur in breast CA or immobilized pts
Halogenated derivative of testosterone with upto 5 times activity of methyltestosterone
Points of recommendation
- This medicine does not help you to be better at sports.
- If you have high blood sugar (diabetes), you will need to watch your blood sugar closely.
- Have blood work checked as you have been told by the doctor. Talk with the doctor.
- This medicine may affect certain lab tests. Tell all of your health care providers and lab workers that you take
- If you are taking warfarin, talk with your doctor. You may need to have your blood work checked more closely while you are taking it with fluoxymesterone.
- This medicine is an anabolic steroid. Anabolic steroid drugs have been abused and misused before. Anabolic steroid abuse can lead to dependence and very bad health problems. These health problems include heart or blood vessel problems, stroke, liver problems, and mental or mood problems. Talk with the doctor.
- This medicine may affect sperm in men. This may affect being able to father a child. Talk with the doctor.
- If you are 65 or older, use fluoxymesterone with care. You could have more side effects.
- This medicine may affect growth in children and teens in some cases. They may need regular growth checks. Talk with the doctor.
- This medicine may cause harm to the unborn baby if you take it while you are pregnant. If you are pregnant or you get pregnant while taking fluoxymesterone, call your doctor right away.
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