Doxazosin side effects

Side effects
Placebo controlled clinical trials Benign Prostatic Hyperplasia Hypertension Controlled hypertension clinical trials Controlled or open, short or long term clinical studies, including international studies Postmarketing experience ---

Benign Prostatic Hyperplasia
The incidence of adverse events has been ascertained from worldwide clinical trials in 965 BPH patients. The incidence rates are based on combined data from seven placebo-controlled trials involving once daily administration of Doxazosin mesylate in doses of 1-16 mg in hypertensives and 0.5-8 mg in normotensives. The adverse events when the incidence in the Doxazosin mesylate group was at least 1% are summarized in Table 3. No significant difference in the incidence of adverse events compared to placebo was seen except for dizziness, fatigue, hypotension, edema and dyspnea. Dizziness and dyspnea appeared to be dose-related.

In these placebo-controlled studies of 665 Doxazosin mesylate patients, treated for a mean of 85 days, additional adverse reactions have been reported. These are less than 1% and not distinguishable from those that occurred in the placebo group. Adverse reactions with an incidence of less than 1% but of clinical interest are (Doxazosin mesylate vs. placebo)

Cardiovascular System: angina pectoris (0.6% vs. 0.7%), postural hypotension (0.3% vs. 0.3%), syncope (0.5% vs. 0.0%), tachycardia (0.9% vs. 0.0%);

Urogenital System: dysuria (0.5% vs. 1.3%), and

Psychiatric Disorders: libido decreased (0.8% vs. 0.3%).

The safety profile in patients treated for up to three years was similar to that in the placebo-controlled studies.

The majority of adverse experiences with Doxazosin mesylate were mild.

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Hypertension
Doxazosin mesylate has been administered to approximately 4000 hypertensive patients, of whom 1679 were included in the hypertension clinical development program. In that program, minor adverse effects were frequent, but led to discontinuation of treatment in only 7% of patients. In placebo-controlled studies adverse effects occurred in 49% and 40% of patients in the Doxazosin and placebo groups, respectively, and led to discontinuation in 2% of patients in each group. The major reasons for discontinuation were postural effects (2%), edema, malaise / fatigue, and some heart rate disturbance, each about 0.7%.

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Controlled hypertension clinical trials
In controlled hypertension clinical trials directly comparing Doxazosin mesylate to placebo there was no significant difference in the incidence of side effects, except for dizziness (including postural), weight gain, somnolence and fatigue / malaise. Postural effects and edema appeared to be dose related. The prevalence rates presented below are based on combined data from placebo-controlled studies involving once daily administration of Doxazosin at doses ranging from 1-16 mg. Adverse experiences (possibly/probably related) reported for patients in these hypertension studies where the prevalence rate in the Doxazosin group was at least 0.5% or where the reaction is of particular interest.

Additional adverse reactions have been reported, but these are, in general, not distinguishable from symptoms that might have occurred in the absence of exposure to Doxazosin.

The following adverse reactions occurred with a frequency of between 0.5% and 1%:


 * syncope
 * hypoesthesia
 * increased sweating
 * agitation
 * increased weight

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Controlled or open, short or long term clinical studies, including international studies
The following additional adverse reactions were reported by <0.5% of 3960 patients who received Doxazosin in controlled or open, short- or long- term clinical studies, including international studies.

Cardiovascular System


 * angina pectoris
 * myocardial infarction
 * cerebrovascular accident

Autonomic Nervous System


 * pallor

Metabolic:


 * thirst
 * gout
 * hypokalemia

Hematopoietic:


 * lymphadenopathy
 * purpura

Reproductive System:


 * breast pain

Skin Disorders:


 * alopecia
 * dry skin
 * eczema

Central Nervous System:


 * paresis
 * tremor
 * twitching
 * confusion
 * migraine
 * impaired concentration

Psychiatric:


 * paroniria
 * amnesia,
 * emotional lability
 * abnormal thinking
 * depersonalization

Special Senses:


 * parosmia
 * earache
 * taste perversion
 * photophobia
 * abnormal lacrimation

Gastrointestinal System:


 * increased appetite
 * anorexia
 * fecal incontinence
 * gastroenteritis

Respiratory System:


 * bronchospasm
 * sinusitis
 * coughing
 * pharyngitis

Urinary System:


 * renal calculus

General Body System:


 * hot flushes
 * back pain
 * infection
 * fever/rigors,
 * decreased weight
 * influenza-like symptoms

Doxazosin mesylate has not been associated with any clinically significant changes in routine biochemical tests. No clinically relevant adverse effects were noted on serum potassium, serum glucose, uric acid, blood urea nitrogen, creatinine or liver function tests. Doxazosin mesylate has been associated with decreases in white blood cell counts.

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Postmarketing experience
In post-marketing experience the following additional adverse reactions have been reported:

Autonomic Nervous System:


 * priapism

Central Nervous System:


 * hypoesthesia

Endocrine System:


 * gynecomastia

Gastrointestinal System:


 * vomiting

General Body System:


 * allergic reaction

Heart Rate/Rhythm:


 * bradycardia

Hematopoietic:


 * leukopenia,
 * thrombocytopenia;

Liver/Biliary System:


 * hepatitis,
 * hepatitis cholestatic;

Respiratory System:


 * bronchospasm aggravated

Skin Disorders:


 * urticaria

Urinary System:


 * hematuria
 * micturition disorder
 * micturition frequency
 * nocturia

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