Terazosin

Registered South African indications: 

• Hypertension
• Benign prostatic hypertrophy

Contraindications

• Hypersensitivity to the active ingredient or to any of its excipients 
• Known sensitivity to other alpha adrenoceptor blockers
• History of micturition syncope

Cautions

• Pregnancy
• Breastfeeding
• Renal impairment
• Hepatic impairment
• Anuria
• Overflow incontinence
• Pulmonary oedema due to aortic or mitral valve stenosis
• High output cardiac insufficiency
• Right-sided cardiac insufficiency due to pulmonary embolism or pericardial effusion
• Left-sided cardiac insufficiency with low filling-pressure
• Severe coronary heart disease
• Intraoperable floppy iris syndrome 
• Galactose intolerance
• Lapp lactase deficiency
• Glucose-galactose malabsorption 

Forms avail. in SA and covered in this monograph: tab

Hypertension - mild to moderate

• Oral (tab): Initial: 1mg, dly at night; Titrate by doubling dose at weekly intervals; Maintenance: 2-20mg, dly at night

Symptomatic treatment of urinary obstruction caused by benign prostatic hypertrophy

• Oral (tab): Initial: 1mg, dly at night; Titrate by doubling dose at weekly intervals; Maintenance: 5-10mg, dly at night; Max: 20mg/24hrs

If the drug is discontinued for several days or longer, therapy should be reinstituted using initial dosing regime

Not established for use in children

Pregnancy

• Caution
• Terazosin hydrochloride was not teratogenic in either rats or rabbits when administered at oral doses up to 1330 and 165 times, respectively, the maximum recommended human dose. Foetal resorptions occurred in rats dosed with 480mg/kg/day, approximately 1330 times the maximum recommended human dose. Increased fetal resorptions, decreased fetal weight and an increased number of supernumerary ribs were observed in offspring of rabbits dosed with 165 times the maximum recommended human dose. These findings (in both species) were most likely secondary to maternal toxicity. Although no teratogenic effects were seen in animal testing, the safety of terazosin use during pregnancy or during lactation has not yet been established. Furthermore, data from animal studies show that terazosin may increase the duration of pregnancy or inhibit labour. Therefore, terazosin should not be used in pregnancy unless the potential benefit outweighs the risk

Breastfeeding

• Caution
• It is not known whether terazosin is excreted in breast milk. Because many drugs are excreted in breast milk, caution should be exercised when terazosin hydrochloride is administered to a nursing woman

Renal Impairment

• Caution; no dose adjustment recommended

Hepatic Impairment

• Mild to moderate: Caution; no dose adjustment recommended
• Severe: Caution; no information available

Elderly

• No dose adjustment recommended

Porphyria Information

• Probably not porphyrinogenic (PNP)

Drugs in Sport

• Permitted - No warnings

Central Nervous System Disorders

• Depression
• Nervousness
• Anxiety
• Insomnia
• Dizziness
• Somnolence
• Headache
• Paraesthesia
• Vertigo
• Asthenia

Cardiovascular Disorders

• Palpitations
• Tachycardia
• Arrhythmia
• Atrial fibrillation
• Postural hypotension
• Syncope
• Vasodilatation
• Peripheral oedema
• Chest pain

Respiratory Disorders

• Nasal congestion
• Rhinitis
• Dyspnoea
• Sinusitis
• Bronchitis
• Epistaxis
• Flu symptoms
• Pharyngitis
• Cold symptoms
• Cough

Gastrointestinal System Disorders

• Nausea and vomiting
• Abdominal pain
• Constipation
• Diarrhoea
• Dry mouth
• Dyspepsia
• Flatulence

Genitourinary Disorders

• Pollakiuria
• Urinary tract infection
• Urinary incontinence
• Decreased libido
• Erectile dysfunction
• Priapism

Endocrine and Metabolic Disorders

• Increased weight

Musculoskeletal Disorders

• Back pain
• Pain in extremity
• Neck pain
• Shoulder pain
• Gout
• Arthralgia
• Arthritis
• Joint disorders
• Myalgia

Skin and Subcutaneous Tissue Disorders

• Pruritus
• Rash
• Hyperhidrosis
• Angioedema
• Facial oedema

Immune, Blood and Lymphatic System Disorders

• Thrombocytopenia
• Anaphylactoid reaction
• Decreased haematocrit
• Decreased haemoglobin
• Decreased white blood cell count
• Decreased total protein 
• Decreased blood albumin
• Pyrexia

Sensory Disorders

• Blurred vision
• Amblyopia
• Visual impairment
• Conjunctivitis
• Tinnitus

• Angiotensin-converting enzyme inhibitors
• Diuretics
• Antihypertensive agents
• Phosphodiesterase-5-inhibitors 

None routine

Postural Hypotension

• Postural hypotension has been reported to occur in patients receiving terazosin for the symptomatic treatment of urinary obstruction caused by BPH. In these cases, the incidence of postural hypotensive events was greater in patients aged 65 years and over (5.6%) than those aged less than 65 years (2.6%)

Terazosin is a selective alpha-1 receptor antagonist, which causes relaxation of peripheral blood vessels and decrease in blood pressure.

Tablet 1mg

• Hytrin (Abbott) originator

Tablet 2mg

• Hytrin (Abbott) originator

Tablet 5mg

• Hytrin (Abbott) originator

Tablet 10mg

• Hytrin (Abbott) originator