Restore urinary flow with doxazosin: An established therapy for benign prostatic hyperplasia
Benign prostatic hyperplasia (BPH) is characterized by an enlargement of the prostate gland that can lead to compression of the urethra.1 Patients often experience lower urinary tract symptoms (LUTS), which are typically classified as either voiding or storage symptoms.1
Over 60% of men will experience any LUTS.2 Although Asian men typically have smaller prostates compared with Western men, Asians experience similar or higher rates of LUTS that can impact sexual function and quality of life (QoL).1,3
Prevalence of BPH
Practicing clinicians should be vigilant of benign prostatic hyperplasia (BPH) among men, a common condition that may become more prevalent with the increasing aging population in Asia Pacific.1,4
While age and prostate volume are associated with BPH, newer evidence also suggests metabolic syndrome is associated with increasing frequency and severity of LUTS.4,5
Doxazosin (Cardura® XL, Pfizer) is indicated for the treatment of clinical symptoms in BPH and for reduced urinary flow associated with BPH.8 Guidelines from both the American Urological Association (AUA) and the European Association of Urology (EAU) recommend doxazosin as a first-line treatment option after lifestyle modification for patients with LUTS suggestive of BPH due to its rapid onset of action, established efficacy, and low rate and severity of adverse events.6,7 Until now, doxazosin remains one of the most efficacious and well tolerated options for relieving symptoms and improving QoL in patients with BPH.6
Abbreviated Prescribing Information1
Composition: Doxazosin-Mesylate GITS Indications: For the treatment of hypertension and can be used as the initial agent to control blood pressure in the majority of patients. In patients not adequately controlled on a single antihypertensive agent, doxazosin may be used in combination with a thiazide diuretic, a beta-blocker, a calcium antagonist or an angiotensin-converting enzyme inhibitor. Indicated for the treatment of clinical symptoms in either hypertensive or normotensive patients with benign prostatic hyperplasia (BPH) and for reduced urinary flow associated with BPH. Recommended dosage: Initial dose is 4mg once daily. The optimal effect of doxazosin may take up to 4 weeks. If necessary, dosage may be increased following this period to the maximum recommended dose of 8mg once daily. Contraindications: Contraindicated in patients with a known hypersensitivity to quinazolines, doxazosin, or any of the inert ingredients. Special warning and precautions for use: Postural Hypotension/Syncope: Patients should be advised how to avoid symptoms resulting from postural hypotension and what measures to take and be cautioned to avoid situations where injury could result should dizziness or weakness occur during the initiation of doxazosin therapy. Doxazosin should be administered with caution in concomitant usage with PDE-5 inhibitors as it may lead to symptomatic hypotension and in patients with evidence of impaired hepatic function or in patients with pre-existing severe GI narrowing (pathologic or iatrogenic). Intraoperative Floppy Iris Syndrome (IFIS): Current or past use of alpha blockers should be made known to the ophthalmologic surgeon in advance of surgery. Priapism: In the event of an erection that persists longer than 4 hours, the patient should seeks immediate medical assistance. Information to patients: Patients should be informed that doxazosin GITS should be swallowed whole. Patients should not chew, divide or crush the tablets. Common side effects: Hypertension: Palpitation, tachycardia, vertigo, abdominal pain, dry mouth, nausea, asthenia, chest pain, peripheral edema, back pain, myalgia, postural hypotension, dizziness, headache, bronchitis, coughing, pruritus, cystitis, and urinary incontinence. Benign Prostatic Hyperplasia: Vertigo, asthenia, peripheral edema, abdominal pain, dyspepsia, nausea, influenza-like symptoms, respiratory tract infection, urinary tract infection, back pain, myalgia, dizziness, headache, somnolence, bronchitis, dyspnea, rhinitis, hypotension, postural hypotension. Formulation and preparation: 4mg tablets in pack of 100’s.
1. Pfizer (Malaysia) Cardura XL Prescribing Information: 23 March 2015
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