Pharmacology Flashcards
Medications Used for BPH
Alpha-1 blockers
5-alpha-reductase inhibitors
Combo: Dutasterid-Tamulosin (Jalyn)
Tadalafil (Cialis)
Examples of Alpha-1 Blockers
Terazosin (Hytrin) Doxazosin (Cardura) Alfuzosin (Uroxatrol) Tamsulosin (Flomax) Silodosin (Rapaflo)
MOA of Alpha-1 Blockers
Relax smooth muscle in the bladder neck & the prostatic capsule & prostatic urethra
Reason for Alpha-1 Blockers
Short & long term symptom management
Where are alpha-1 receptors located?
Base of the bladder
In the prostate
SE of Alpha-1 Blockers
Dizziness Orthostatic hypotension Asthenia (muscle weakness) Nasal congestion Problems with ejaculation (especially with Tamsulosin (Flomax))
Alpha-1 Blockers with More BP Effects
Terozosin (Hytrin)
Doxazosin (Cardura)
Alpha-1 Blockers with Less BP Effects
Tamsulosin (Flomax)
Alfuzosin (Uroxatrol)
Silodosin (Rapaflo_
Examples of 5-alpha-reductase Inhibitors
Finasteride (Proscar)
Dutasteride (Avodart)
Benefits of 5-Alpha-Reductase Inhibitors
Long term decrease in prostate size & decreased need for prostatic surgery
MOA of 5-Alpha-Reductase Inhibitors
Competitive inhibitor of both tissue & hepatic 5-alpha reductase
Inhibition of the conversion of testosterone to DHT & suppress serum DHT levels
Decreases prostatic size
Efficacy of 5-alpha-reductase Inhibitors
May be up to a year to notice reduction in symptoms
Reduce symptoms scores
Increase maximum urinary flow rate
Reduction in mean prostatic volume
Decreased need for surgery
Decreased development of acute urinary retention
Major SE of 5-Alpha-Reductase Inhibitors
Decreased libido
Ejaculatory or erectile problems
Decreases serum PSA by 50%
Cialis for BPH
Blocks PDE5 in the prostate & bladder
Medications not to Use with Cialis
Nitrates
Alpha-1 Blockers
Medications for Erectile Dysfunction
Alprostadil Tadalafil (Cialis) Vardenafil (Levitra) Sildenafil (Viagra) Avanafil (Stendra
Drug Category for Alprostadil (Caverject, Muse)
Prostaglandin
Vasodilator
MOA of Alprostadil (Caverject, Muse)
Vasodilation on vascular & smooth muscles
Relaxes trabecular smooth muscle by dilation of cavernosal arteries
Onset & Duration of Action of Alprostadil (Caverject, Muse)
Onset: 5-20 minutes
Duration:
Contraindications of Alprostadil (Caverject, Muse)
Conditions that predispose the patient to priapism
Anatomic or fibrotic conditions of the penis
For pellets: urethral stricture, perineal pain
SE of Alprostadil (Caverject, Muse)
Syncope
Priapism
May cause BP lowering
Phosphodiasterase Inhibitors
Tadalafil (Cialis)
Vardenafil (Levitra)
Sildenafil (Viagra)
Avanafil (Stendra)
MOA of Phosphodiasterase Inhibitors
Release of nitric oxide (NO) during sexual stimulation
NO produces smooth muscle relaxation & inflow of blood
Enhances the effect of NO by inhibiting phosphodiesterase type 6 (PDE-5)
Do not directly cause penile erections
Contraindications of Phosphodiasterase Inhibitors
Men taking nitrates
Caution with alpha-1 blockers (severe hypotension)
SE of Phosphodiesterase Inhibitors
Severe hypotension Flushing Headaches Dyspepsia Transient blue vision with sildenafil (Viagra) Increase risk for non-arteritis ischemic optic neuropathy Hearing loss Priapism
Administration of Phosphodiesterase Inhibitors
Take 60 minutes prior to intercourse
Food/alcohol delay onset of action in sildenafil (Viagra) & vardenafil (Levitra)
Duration of Action of Phosphodiesterase Inhibitors
Tadalafil (Cialis): up to 36 hours
All others: 8-12 hours
Define Primary Hypogonadism
Testes fail to produce testosterone
Define Secondary Hypogonadism
Pituitary or hypothalamus malfunctino
MOA of Testosterone Replacement
Bind to the androgen receptor
Act in tissues that express the enzyme 5-alpha reductase
Can act as estrogen after converting to estradiol
Indications for Testosterone Replacement
Decreased libido Decreased AM erections Loss of body hair Low bone density Gynecomastia Small testes Decreased muscle mass
Goal of Testosterone Replacement
Return testosterone level back to normal range
Things to do Prior to Starting Testosterone Replacement
Screen for prostate cancer
Screen for erythrocytosis
Make sure sleep apnea is present
SE of Testosterone Replacement
Polycythemia Worsening of BPH symptoms Acne Increase in PSA Oral & prolonged IM doses associated with liver issues Increased risk of prostate cancer Decreased spermatogenesis Fluid retention Worsening of sleep apnea Possible increased risk of CV events
Contraindications of Testosterone Replacement Therapy
CV events in the last 6 months Known prostate cancer Known breast cancer Severe lower urinary tract symptoms HCT >50% Untreated severe sleep apnea PSA >4 mcg/L PSA >3 mcg/L with risk factors for prostate cancer
Routes of Testosterone Replacement
Oral (hepatic SE) Buccal tablet (BID) Subcutaneous pellet (replace 3-6 months) Nasal gel (TID) Parenteral: long acting Transdermal/topical: patch, gel
Which Formulation to Use
Transdermal gel (1st): well tolerated Some prefer injections
Monitoring During Testosterone Replacement
Serum testosterone
Serum LH: primary hypogonadism
Bone density
Hematocrit: 3-6 months after starting therapy, then yearly
PSA prior to initiating therapy: 3-6 months after starting therapy, then yearly
DRE: 3-6 months after starting therapy, then yearly
Examples of Gels
AndroGel: metered pump or packets
Testim
Fortesta
Axiron
Adroderm
Worn on arm or torso
Significant skin irritation
IM Testosterone
Testosterone enanthate (Delatestry) Testosterone cypionate (Depo-Testosterone) Gluteal injections
Urinary Tract Analgesic
Phenazopyridine (Pyridium)
Pentosan (Elmiron)
Benefit of Phenazopyridine (Pyridium)
Symptomatic relief of urinary burning, itching, frequency, & urgency associated with UTI or post urologic procedures
Contraindication of Urinary Tract Analgesics
GFR
Prescribing Considerations for Urinary Tract Analgesics
Use
SE of Urinary Tract Analgesics
Orange urine
HeadacheDizziness
Stomach cramps
Indications of Pentosan (Elmiron)
Interstitial cystitis
Define Interstitial Cystitis
Inflammation of the wall of the blader
MOA of Pentosan (Elmiron)
Adhere to the bladder wall mucosa where it may act as a buffer to protect the tissues from irritating substances in the urine
Low-molecular weight heparinoid
SE of Pentosan (Elmiron)
Headache Dizziness Alopecia Rash Rectal hemorrhage Diarrhea Nausea Abdominal pain Dyspepsia LFT abnormalities
Medications for Incontinence (Anti-muscarinic Agents)
Oxybutynin (Ditropan) (Ditropan XL) Tolterodine (Detrol) (Detrol LA) Trospium (Sanctura) (Trospium XR) Solifenacin (Vesicare) Darifenacin hydrobromide (Enablex) Fesoterodine (Toviaz)
Treatment of urgency, urgency-predominant mixed or OAB symptoms
Do not use pharmacologic therapy in demented patients
Contraindications for Anti-muscarinic Agents
Gastric retention
Angle closure glaucoma
Neurogenic bladder
MOA of Anti-muscarinic Agents
Increase bladder capacity
Block basal release of acetylcholine during bladder filling resulting in decreased urgency
Prescribing Anti-muscarinic Agents
Extended release agents have lower rates of SE
Start with lowest available dose
Evaluate for response in 4-6 weeks
May respond to one agent & not another
SE of Anti-muscarinic Agents
Dry mouth Constipation Blurred vision to near objects Tachycardia Drowsiness Decreased cognitive function Dizziness
Considerations for Prescribing Anti-muscarinic Agents
Hepatic metabolism at CYP450 Renal failure Liver failiure Cognitive impairment Combinations to avoid AE to avoid Generally prescribe ER or transdermal formulations
Drug Combinations to Avoid with Anti-muscarinic Agents
1st generation antihistamines Muscle relaxants Some anti-psychotics TCAs Ipratropium (Combivent) Tiotropium (Spiriva) Cholinesterase inhibitors (donepezil, rivastigmine, glantamine) Triospium & ETOH within 2 hours Mirabegron Metoprolol & darifenacin Grapefruit juice (darrifenacin, solifenacin, festerodine, tolerodine)
Set Realistic Expectations Prior to Prescribing Anti-muscarinic Agents
Reduce number of incontinence episodes
30% of patients achieve complete bladder control
Failure of one medication, try another
Common Antibiotics for UTI Treatment
Ciprofloxacin Trimethoprim/sulfamethoxazole (Bactrim/Septra) Nitrofurantoin (Macrodantin) Amoxicillin Ampicillin
Class of Ciprofloxacin
Fluoroquinolones
MOA of Ciprofloxacin
inhibit DNA gyrase & topoisomerase IV necessary for replication of bacteria
Pregnancy Category of Ciprofloxacin
Category C
Black Box Warnings for Ciprofloxacin
Increased risk of tendinitis & tendon rupture
Urologic Indications for Ciprofloxacin
Cystitis
UTI
Prostatitis
Class of Trimethoprim/sulfamethoxazole (Bactrim/Septra)
Sulfa drugs
MOA of Trimethoprim/sulfamethoxazole (Bactrim/Septra)
Folic acid synthesis inhibitors
Inhibits dihydropteroate synthetase
Inhibits dihydrofolate reductase
Pregnancy Category of Trimethoprim/sulfamethoxazole (Bactrim/Septra)
Category C
Nitrofurantoin (Macrodantin) in the Setting of CKD & Decreased CrCl
Can cause peripheral neuropathy
Don’t use with CrCl
MOA of Nitrofurantoin (Macrodantin)
Disrupt bacterial cell wall synthesis through inhibition of bacterial enzymes
Pregnancy Category of Nitrofurantoin (Macrodantin)
Category B
Contraindicated at term
Urologic Indications of Nitrofurantoin (Macrodantin)
UTIs
Class of Amoxicillin
Secondary generation penicillin
MOA of Amoxicillin
Bactericidal to growing bacteria
Interferes with transpeptidation of cell wall synthesis
Pregnancy Category of Amoxicillin
Category B
Class of Ampicillin
Secondary generation penicillin
MOA of Ampicillin
Bactericidal to growing bacteria
Interferes with transpeptidation of cell wall synthesis
Pregnancy Category of Ampicillin
Category B