DOXAZOSIN

Posology Adults:

Hypertension Doxazosin is taken in a once daily regimen. 4). Dosage may then be increased to 2mg after an additional one or two weeks of therapy and thereafter, if necessary to 4mg. The majority of patients who respond to Doxazosin tablets will do so at a dose of 4mg or less.

Dosage can be further increased if necessary to 8mg or the maximum recommended dose of 16mg. 4). Depending on the individual patient’s urodynamics and BPH symptomatology dosage may then be increased to 2mg and thereafter to 4mg and up to the maximum recommended dose of 8mg.

The recommended titration interval is 1-2 weeks. The usual recommended dose is 2-4mg daily.

Elderly:

Normal adult dosage Paediatric Population The safety and efficacy of Doxazosin tablets in children and adolescents have not been established.

Renal impairment:

Since there is no change in pharmacokinetics in patients with impaired renal function, the usual adult dose of Doxazosin tablets is recommended. Doxazosin tablets is not dialysable. g. cimetidine). 2).

Method of administration:

For oral administration. Doxazosin tablets may be administered in the morning or the evening.

Hypertension:

In clinical trials involving patients with hypertension, the most common reactions associated with doxazosin therapy were of a postural type (rarely associated with fainting) or non-specific.

Benign prostatic hyperplasia:

Experience in controlled clinical trials in BPH indicates a similar adverse event profile to that seen in hypertension. The following undesirable effects have been observed and reported during treatment with doxazosin with the following frequencies: Very common (≥1/10); common (≥1/100 to <1/10); uncommon (≥1/1,000 to <1/100); rare (≥1/10,000 to <1/1,000); very rare (<1/10,000).

4) Ear and labyrinth disorders Vertigo Tinnitus Cardiac disorders Palpitation, tachycardia Angina pectoris, myocardial infarction Bradycardia cardiac arrhythmias Vascular disorders Hypotension, postural hypotension Hot flushes Respiratory, thoracic and mediastinal disorders Bronchitis, cough, dyspnea, rhinitis Epistaxis Bronchosp asm Gastrointestinal disorders Abdominal pain, dyspepsia, dry mouth, nausea Constipation, flatulence, vomiting, gastroenteritis diarrhoea Hepato-biliary disorders Abnormal liver function tests Cholestasis , hepatitis, jaundice Skin and subcutaneous tissue disorders Pruritus Skin rash Urticaria alopecia, purpura Musculoskeletal, connective tissue and bone disorders Back pain, myalgia Arthralgia Muscle cramps, muscle weakness Renal and urinary disorders Cystitis, urinary incontinence Dysuria, micturition frequency, hematuria Polyuria Increased diuresis, micturition disorder, nocturia Reproductive system and breast disorders Impotence Gynecoma stia, priapism Retrograde ejaculation General disorders and administration site conditions Asthenia, chest pain, influenza- like symptoms, peripheral oedema Pain, facial oedema Fatigue, malaise Investigations Weight increase Reporting of suspected adverse reactions Reporting suspected adverse reactions after authorisation of the medicinal product is important.

2). Therefore, it is prudent medical practice to monitor blood pressure on initiation of therapy to minimise the potential for postural effects. When instituting therapy with any effective alpha-blocker, the patient should be advised how to avoid symptoms resulting from postural hypotension and what measures to take should they develop.

The patient should be cautioned to avoid situations where injury could result, should dizziness or weakness occur during the initiation of doxazosin therapy. 2). Since there is no clinical experience in patients with severe hepatic impairment, use in these patients is not recommended.

Use with PDE-5 inhibitors:

Concomitant administration of doxazosin with phosphodiesterase-5-inhibitors (eg sildenafil, tadalafil, and vardenafil) should be done with caution as both drugs have vasodilating effects and may lead to symptomatic hypotension in some patients.

To reduce the risk of orthostatic hypotension it is recommended to initiate the treatment with phosphodiesterase-5-inhibitors only if the patient is hemodynamically stabilized on alpha-blocker therapy. Furthermore, it is recommended to initiate phosphodiesterase-5-inhibitor treatment with the lowest possible dose and to respect a 6-hour time interval from intake of doxazosin.

No studies have been conducted with doxazosin prolonged release formulations.

Use in patients undergoing cataract surgery:

The ‘Intraoperative Floppy Iris Syndrome’ (IFIS, a variant of small pupil syndrome) has been observed during cataract surgery in some patients on or previously treated with tamsulosin. Isolated reports have also been received with other alpha-1 blockers and the possibility of a class effect cannot be excluded.

As IFIS may lead to increased procedural complications during the cataract operation current or past use of alpha-1 blockers should be made known to the ophthalmic surgeon in advance of surgery. Priapism Prolonged erections and priapism have been reported with alpha-1 blockers including doxazosin in post marketing experience.

g. 1. 2 Patients with a history of orthostatic hypotension 3 Patients with benign prostatic hyperplasia and concomitant congestion of the upper urinary tract, chronic urinary tract infection or bladder stones. 6). 5 Patients with hypotension (For benign prostatic hyperplasia indication only).

Doxazosin is contraindicated as monotherapy in patients with either overflow bladder or anuria with or without progressive renal insufficiency.