Pilocarpine Hydrochloride, commonly referred to as Pilocarpine HCl, is the hydrochloride salt of pilocarpine and a pharmaceutical active ingredient belonging to the cholinergic or parasympathomimetic class. Pilocarpine HCl CAS Number 54-71-7 identifies the hydrochloride form, which has the molecular formula C11H17ClN2O2 and a molecular weight of 244.72 g/mol. NIST and PubChem both identify CAS 54-71-7 for pilocarpine hydrochloride.
Pilocarpine hydrochloride is a hygroscopic pharmaceutical substance generally described as a white or almost white crystalline powder or colorless crystals. Current pharmaceutical labeling describes it as very soluble in water and freely soluble in ethanol (96%), while other official labels describe it more generally as soluble in water and alcohol and virtually insoluble in most non-polar solvents.
The API is particularly important because pilocarpine is a predominantly muscarinic cholinergic agonist. Its pharmacological activity can stimulate exocrine gland secretion, including salivary and lacrimal secretions. Depending on the dosage form and indication, pilocarpine hydrochloride is used in pharmaceutical products associated with dry mouth and ocular conditions involving increased intraocular pressure. PubChem identifies pilocarpine hydrochloride as the hydrochloride salt of (+)-pilocarpine and describes its cholinergic agonist activity.
Pilocarpine hydrochloride has a defined stereochemical structure and should not be confused with isopilocarpine hydrochloride, which is a different stereoisomeric substance. PubChem identifies pilocarpine itself as having the stereochemical configuration corresponding to the active pilocarpine molecule, while separate records exist for isopilocarpine hydrochloride.
This distinction is relevant for pharmaceutical API manufacturing because stereochemical identity can affect the biological properties of an active pharmaceutical ingredient. Appropriate identity and purity testing should therefore confirm that the API corresponds to the intended pilocarpine hydrochloride form.
| Parameter | Specification |
|---|---|
| Appearance | white to off-white crystalline powder |
| Identification | IR & HPLC compliant |
| Assay (HPLC) | 98.0% – 102.0% |
| Loss on Drying | NMT 3.0% |
| Residue on Ignition | NMT 0.1% |
| Individual Impurity | NMT 0.1% |
| Total Impurities | NMT 1.0% |
| Water Content | NMT 3.0% |