Inreq (Tamsulosin Hydrochloride)

Tamsulosin Hydrochloride acts on the alpha‑1 adrenergic receptors of the prostate and bladder neck, addressing conditions within the benign prostatic hyperplasia (BPH) spectrum.

• Benign prostatic hyperplasia (BPH): reduces smooth muscle tone in the prostate and improves urinary flow.
• Lower urinary tract symptoms (LUTS) associated with BPH: alleviates urgency, frequency, and nocturia.
• Urinary obstruction due to BPH: facilitates bladder emptying and reduces residual volume.
• Prostatic bladder neck dysfunction: relaxes the bladder neck to ease urine passage.

• Tamsulosin selectively blocks alpha‑1A and alpha‑1D adrenergic receptors located in the prostate, bladder neck, and urethra. By antagonizing these receptors, it prevents norepinephrine‑mediated smooth‑muscle contraction, leading to relaxation of the prostate and bladder neck. This reduction in smooth‑muscle tone decreases urethral resistance, thereby improving urinary flow and relieving symptoms of BPH. The effect is dose‑dependent and occurs without significant impact on systemic blood pressure in most patients.

Tamsulosin may cause a range of adverse reactions, which are categorized by frequency and severity.

Common Side Effects

• Dizziness
• Headache
• Nasal congestion
• Abnormal ejaculation (reduced volume or retrograde)

Serious or Rare Side Effects

• Severe hypotension or syncope
• Allergic reactions (rash, angioedema)
• Priapism (rare prolonged erection)

Before initiating therapy with Tamsulosin, several precautionary measures should be considered to ensure safe use.

• Cardiovascular assessment: evaluate baseline blood pressure and history of orthostatic hypotension.
• Hepatic function: use caution in patients with moderate to severe liver impairment.
• Concomitant alpha‑blockers: avoid simultaneous use due to additive hypotensive effect.
• CYP3A4 inhibitors: monitor for increased drug exposure when strong inhibitors are co‑administered.
• Hypersensitivity: discontinue if signs of allergic reaction appear.
• Store at ambient temperature: keep below 25 °C in the original packaging, protected from moisture.

Tamsulosin can interact with other medicines, and awareness of these interactions helps manage risk.

Major Interactions (Avoid)

• Strong CYP3A4 inhibitors (e.g., ketoconazole, itraconazole): may markedly increase plasma concentrations.
• Other alpha‑adrenergic antagonists (e.g., prazosin, doxazosin): can cause additive hypotension.
• Phosphodiesterase‑5 inhibitors (e.g., sildenafil, tadalafil): increase risk of symptomatic hypotension.

Moderate Interactions (Monitor Closely)

• CYP3A4 inducers (e.g., rifampin, carbamazepine): may reduce tamsulosin efficacy.
• Warfarin: potential increase in INR, requiring closer monitoring.
• Diuretics: may enhance orthostatic blood pressure changes.