51. BPH Flashcards
Testosterone is metabolized to ____ by ____
dihydrotestosterone (DHT) by 5 alpha-reductase
Benign prostatic hyperplasia (BPH) results from overgrowth of the ___ and ___ of the prostate gland
Stromal and epithelial cells
What are some drugs that can worsen BPH?
Centrally-acting anticholinergics (e.g. benztropine)
Drugs with anticholinergic effects
- antihistamines (e.g. diphenhydramine)
- Decongestants (e.g. pseudoephedrine)
- Phenothiazines (e.g. prochlorperazine)
- TCAs (e.g. amitriptyline)
Caffeine
Diuretics
SNRIs
Testosterone products
Diagnosis of BPH includes ___
digital rectal exam (DRE) to determine size of prostate and identify any lumps or nodules
Urinalysis and serum prostate-specific antigen (PSA) to rule out other conditions
S/sx of BPH are mainly lower urinary tract symptoms. What are some examples
Hesitancy, intermittent urine flow, straining or weak stream
Urgency, leaking or dribbling
Frequency, especially nocturia
Incomplete emptying of the bladder
Bladder outlet obstruction
BPH rarely causes more severe symptoms but if blockage is severe, urine could back up into the kidneys and result in ___
acute renal failure
Treatment for mild BPH disease vs Moderate/severe BPH disease
Mild = watchful waiting and monitoring
Moderate/severe = meds or surgery (transurethral resection of the prostate (TURP))
What natural product is used for BPH (although unlikely to be effective)?
Saw palmetto
What natural products is used for prostate cancer prevention
Lycopene
5 alpha-reductase inhibitors work by ___ but they have delayed onset
decreasing prostate size
When should 5 alpha-reductase inhibitors NOT be used?
Men who have bladder outlet obstruction symptoms w/o prostate nelargement
What med regimen would be fitting for patients with BPH and erectile dysfunction?
PDE-5i tadalafil ± finasteride
MOA Alpha-1 blocker
Inhibit alpha-1 adrenergic receptors»_space; relaxation of smooth muscle in prostate and bladder neck»_space; reduces bladder outlet obstruction and improves urinary flow
What type of alpha-1 receptor is primarily found in the prostate?
Alpha-1A
Note: Alpha-1B and Alpha-1D are primarily found in the heart and arteries
What are examples of selective alpha-1A blockers?
Tamsulosin, alfuzosin, sildosin
What are examples of non-selective alpha-1 blockers?
Terazosin, doxazosin
Which type of alpha-1 blockers have more side effects: selective or non-selective?
Non-selective (terazosin, doxazosin)
Patients using alpha-blockers are at risk of developing ___ during cataract surgery. If cataract surgery is planned, can alpha-blockers still be used?
Intraoperative floppy iris syndrome (IFIS)
Alpha-blocker treatment should be delayed until surgery has been completed
Note: alpha-1 receptors are present on the iris dilator muscle in the eye
What alpha blockers used in BPH are recommended to be given at bedtime and titrated slowly
Non-selective alpha-1 blockers: Doxazosin (Cardura, Cardura XL) and terazosin
Warnings for alpha blockers used in BPH
Orthostatic hypotension/syncope (if dosage is increased too rapidly, another antiHTN med, or PDE-5i used)
IFIS in cataract surgery
Priapism (prolonged erection, seek med attention if >4 hrs)
Angina (d/c if angina begin or worsens)
Starting dose for tamsulosin (Flomax)
0.4mg daily
Side effects for alpha-1 blockers
Dizziness, fatigue, HA, abnormal ejaculation (esp with tamsulosin and silodosin), fluid retention, rhinitis (tamsulosin)
Why are non-selective alpha-1 blockers recommended to be given at bed time?
To minimize initial “first-dose” effect of orthostasis/dizziness
Alpha-blockers work quickly on LUTS but may take ____ to assess whether beneficial effects have been achieved
4-6 weeks
Alpha blockers work quickly but do not ___
shrink the prostate or change PSA levels
Which alpha-1 blocker can cause retrograde ejaculation in ~30% patients (reversible upon d/c)
Silodosin
Pt is on tadalafil for BPH but may require additional BPH med. Which BPH meds should be avoided?
Alpha-1 blockers (risk of orthostatic hypotension/syncope)
Which alpha-1 blocker can cause QT prolongation?
Alfuzosin (Uroxatral)
MOA 5 alpha-reductase inhibitors
Inhibit 5 alpha-reductase enzyme, which blocks conversion of testosterone to dihydrotestosterone (DHT)
___ is selective for the 5 alpha-reductase type II enzyme (more prevalent within prostate) while ___ inhibits both type I and II
Finasteride
Dutasteride
What is the rationale to use alpha-blockers + 5 alpha-reductase inhibitors?
Improve symptoms
Decrease risk of acute urinary retention
Decrease need for surgery
Alpha-blockers = LUTS
5 alpha-reductase inhibitors = shrink prostate and decrease PSA levels
Indication for 5 alpha-reductase inhibitors
Treatment for symptomatic BPH in men with enlarged prostate
Contraindications for 5 alpha-reductase inhibitors
Women of child bearing potential, pregnancy, children
Side effects of 5 alpha-reductase inhibitors
Impotence, decreased libido, ejaculation disturbances, breast enlargement and tenderness, rash
Note: sexual side effects decrease with time and return to baseline at 1 year of use in some men
Which BPH meds should pregnant women NOT take or handle
5 alpha-reductase inhibitors
5 alpha-reductase inhibitors take ___ for maximal efficacy
6 months or longer
5 alpha-reductase inhibitors affect on BPH
shrink prostate and decrease PSA levels
Which brand name of finasteride is for alopecia
Propecia
Note: do not use Proscar if using Propecia for hair loss
____ is the only PDE-5i that is FDA-approved for treatment of BPH with or w/o ED
Tadalafil
Contraindications for tadalafil (Cialis)
Do NOT use with nitrates or riociguat
Warnings for tadalafil (Cialis)
Impaired color discrimination (dose-related, higher risk with retinitis pigmentosa)
Hearingl oss
Vision loss (can be d/t nonarteritic anterior ischemic optic neuropath NAION)
Hypotension
CVD (seek immediate med help for chest pain)
Priapism (seek emergency med care if erection > 4hr)
Side effects for tadalafil (Cialis)
HA, flushing, dizziness, dyspepsia, muscle/back pain, myalgia, blurred vision, increased sensitivity to light, epistaxis, diarrhea
