Naftopidil is a selective alpha-1 adrenergic receptor antagonist used in pharmaceutical applications related to benign prostatic hyperplasia (BPH) and lower urinary tract symptoms (LUTS).
Naftopidil works primarily by blocking α1-adrenergic receptors in the prostate, bladder neck and urethral smooth muscle. This reduces smooth-muscle tone and can improve urinary flow and relieve symptoms associated with bladder outlet obstruction.
Unlike some α1-blockers, Naftopidil has relatively high affinity for the α1D-adrenoceptor subtype, in addition to activity at other α1-adrenoceptor subtypes. This receptor profile has made it an important compound in urological pharmacology.
Naftopidil is a synthetic pharmaceutical compound with the molecular formula C₂₄H₂₈N₂O₃ and molecular weight 392.49 g/mol.
Naftopidil belongs to the quinoline/phenylpiperazine-related class of α1-adrenergic antagonists. It is primarily associated with the treatment of urinary symptoms caused by benign prostatic hyperplasia.
The pharmacological action of Naftopidil involves relaxation of smooth muscle in the prostate and lower urinary tract, helping reduce resistance to urinary flow.
Naftopidil is primarily associated with urological applications, particularly the management of symptoms related to benign prostatic hyperplasia.
Naftopidil is particularly established as a treatment for BPH-related lower urinary tract symptoms in Japan and several other Asian markets.
For your commercial API page, it is better to describe regulatory indications as market-dependent, rather than implying worldwide approval for a specific indication.
Naftopidil acts by selectively antagonizing α1-adrenergic receptors.
α1 receptors are present in smooth muscle of the prostate, bladder neck and urethra. Activation of these receptors contributes to smooth-muscle contraction and increased resistance to urinary flow.
By blocking these receptors, Naftopidil promotes relaxation of smooth muscle in the lower urinary tract. This can reduce urinary resistance and improve symptoms such as:
Naftopidil also demonstrates relatively strong affinity for the α1D receptor subtype, which is relevant to its pharmacological profile.
| Parameter | Specification |
|---|---|
| Appearance | White crystalline powder or crystals |
| Identification | IR & HPLC compliant |
| Assay (HPLC) | 98.0% – 102.0% |
| Loss on Drying | NMT 1.0% |
| Residue on Ignition | NMT 0.5% |
| Individual Impurity | NMT 0.5% |
| Total Impurities | NMT 1.0% |
| Water Content | NMT 1.0% |