Pseudoephedrine Sulfate is the sulfate salt of pseudoephedrine, a sympathomimetic amine primarily used for its nasal decongestant activity. It produces vasoconstriction in nasal mucosal blood vessels, helping reduce nasal and sinus congestion.
The pharmaceutical substance is a 2:1 salt consisting of two pseudoephedrine molecules and one sulfuric acid molecule. The exact API has CAS 7460-12-0, molecular formula (C₁₀H₁₅NO)₂·H₂SO₄, and molecular weight 428.54 g/mol.
Pseudoephedrine Sulfate is described in the USP-NF as Benzenemethanol, α-[1-(methylamino)ethyl]-, [S-(R,R)]-, sulfate (2:1) (salt)** and (+)-Pseudoephedrine sulfate (2:1) (salt). The USP monograph identifies CAS 7460-12-0 and FDA GSRS UNII Y9DL7QPE6B.
The substance occurs as a crystalline material and has a reported melting range of approximately 174–179°C under the USP test. It has a specific rotation of +56.0° to +59.0° when measured at 50 mg/mL in water.
| Parameter | Details |
|---|---|
| Product Name | Pseudoephedrine Sulfate |
| API Form | Sulfate salt, 2:1 |
| CAS Number | 7460-12-0 |
| Molecular Formula | (C₁₀H₁₅NO)₂·H₂SO₄ |
| Molecular Weight | 428.54 g/mol |
| FDA UNII | Y9DL7QPE6B |
| ChEMBL | CHEMBL3989855 |
| Chemical Class | Sympathomimetic amine |
| Therapeutic Class | Nasal decongestant |
| API Category | Active Pharmaceutical Ingredient |
| Appearance | Crystalline solid |
| Melting Range | 174–179°C |
| pH | 5.0–6.5 in 1 in 20 solution |
| Specific Rotation | +56.0° to +59.0° |
| Water / LOD | NMT 2.0% |
| Residue on Ignition | NMT 0.1% |
| Solubility | Soluble in water; aqueous pharmaceutical salt |
PubChem gives the molecular weight as 428.5 g/mol and confirms CAS 7460-12-0, formula, UNII and sulfate salt composition.
Pseudoephedrine Sulfate is primarily used as a nasal and sinus decongestant. Pseudoephedrine stimulates adrenergic pathways and causes vasoconstriction, reducing swelling of the nasal mucosa and improving nasal airflow.
It is commonly incorporated into pharmaceutical formulations either as a single active ingredient or in combination products with other medicines used for cold, allergy and respiratory symptoms. USP specifically lists Pseudoephedrine Sulfate as an active component in combination oral formulations.
Pseudoephedrine Sulfate has an established USP-NF monograph. The current USP information specifies 98.0–100.5% of pseudoephedrine sulfate, calculated on the dried basis.
The USP identification procedure includes IR spectroscopy, UV-visible spectroscopy and sulfate identification. The monograph also specifies melting range, specific rotation, pH, loss on drying, residue on ignition, chloride and heavy-metal testing.
The USP monograph specifies 98.0–100.5% assay, LOD NMT 2.0%, residue on ignition NMT 0.1%, pH 5.0–6.5, melting range 174–179°C, and specific rotation +56.0° to +59.0°.
For heavy metals, the USP test uses a 10 ppm lead standard, and the Brazilian Pharmacopoeia independently specifies NMT 10 ppm for Pseudoephedrine Sulfate, providing additional support for this numerical value.
For the USP monograph, the official assay is not an HPLC assay. It uses potentiometric titration with 0.1 N perchloric acid, with each mL equivalent to 42.85 mg of Pseudoephedrine Sulfate. Therefore, if your CMS field is named “Assay (HPLC)”, the correct content should still be entered as 98.0–100.5% USP assay, but the method should be described as USP potentiometric titration, not falsely labeled as USP HPLC.
Manufacturing of Pseudoephedrine Sulfate requires control of the sulfate salt composition, stereochemical identity, assay, moisture, inorganic residue, chloride and elemental impurities.
Analytical quality control can include IR, UV-visible spectroscopy, HPLC/TLC impurity testing, potentiometric assay, loss on drying, residue on ignition, specific rotation, pH, chloride and heavy-metal testing. The USP monograph specifically controls the optical rotation because stereochemical identity is an important characteristic of pseudoephedrine.
USP specifies that Pseudoephedrine Sulfate should be preserved in tight, light-resistant containers.
Recommended CMS wording:
Store in tight, light-resistant containers under controlled pharmaceutical storage conditions. Protect from excessive heat, moisture and contamination.
Typical Pseudoephedrine Sulfate API documentation may include:
Pseudoephedrine Sulfate has well-established pharmacopoeial quality requirements. The USP specification provides defined controls for assay, stereochemical identity, pH, moisture, residue on ignition, chloride, heavy metals and physical characteristics.
| Parameter | Specification |
|---|---|
| Appearance | white to off-white crystalline powder |
| Identification | IR & HPLC compliant |
| Assay (HPLC) | 98.0–100.5% |
| Loss on Drying | NMT 2.0% |
| Residue on Ignition | NMT 0.1% |
| Heavy Metals | NMT 10 ppm |
| Specific Rotation | +56.0° to +59.0° |
| Melting Point | 174–179°C |