Fitzy's drugs that decrease steroid concentrations; 4.8 Flashcards
What is the goal of inhibiting LH and FSH secretion, inhibiting 5α-reductase, and inhibiting aromatase?
Decrease steroid concentrations
(LH/FSH inhibition…block upstream event)
(5α-reductase inhibition…no DHT)
(Aromatase inhibition…no estrone or estradiol)
What kind of drugs are used to inhibit LH/FSH secretion?
GnRH analogs
GnRH antagonists
Are goserelin and leuprolide GnRH analogs or GnRH antagonists?
Goserelin and leuprolide are ANALOGS of GnRH
How are goserelin and leuprolide administered?
Continuous
Long-term
How do GnRH analogs work?
Transient increase in steroid hormones (→ flare of symptoms) followed by down regulation (or desensitization) of GnRH receptors → decreased testosterone/estrogen
When are goserelin and leuprolide used?
Advanced prostate cancer
Premenopausal women with ER+ breast cancer
What is an example of a GnRH antagonist?
Degarelix
Centrorelix and ganerelix also…the “relix”es
Does degarelix work faster or slower than goserelin/leuprolide?
Antagonists work faster than agonists…less than 3 days compared to 1-4 months
When is degarelix used?
Assisted reproductive procedures
Prostate cancer
Breast cancer…maybe
Although GnRH antagonists are generally WELL TOLERATED, what types of side effects may be experienced by patients?
Effects of low testosterone
Effects of histamine release (less so with degarelix)
What are dutasteride and finasteride?
Dutasteride and finasteride are 5α-reductase inhibitors (RIDEuctase)
When are 5α-reductase inhibitors used?
BPH
Male-pattern baldness
Prevention of prostate cancer
Are the normal low testosterone side effects experienced dutasteride/finasteride patients?
Yes and no…everything except NO muscle wasting or decrease in bone density
Who should be incredibly careful handling 5α-reductase inhibitor capsules?
Pregnant women…can have dramatic affects on male children
Non-steroidal aromatase inhibitors are reversible. What are examples of non-steroidal aromatase inhibitors?
Aminoglutethimide
Anastrozole
Letrozole
Which of the non-steroidal aromatase inhibitors is a first generation? What else does this drug do?
Aminoglutethimide is a first generation non-steroidal aromatase inhibitor
Also inhibits cholesterol → pregnenolone in adrenal gland
What side effects are potentially seen with aminoglutethimide?
Acutely: mild nausea, fatigue, fever
Delayed: rash, adrenal insufficiency
How should aminoglutethimide induced adrenal insufficiency be treated?
Hydrocortisone
When shouldn’t hydrocortisone be given to an adrenal insufficient patient who is taking aminoglutethimide?
If the body has overcome the block by increasing ACTH…which can cause myelosuppression and can be aggravated by hydrocortisone
Anastrozole and letrozole are 3rd generation aromatase inhibitors. What is an example of a steroidal 3rd generation?
Exemestane
What are the potential side effects of 3rd generation aromatase inhibitors?
Acutely: mild nausea, headache
Delayed: Fatigue, increased appetite, hot flushes; polyarthralgia unique to AIs; decrease in bone density; may IMPROVE lipid numbers