Difenoxin is a synthetic opioid antidiarrheal pharmaceutical active ingredient. It is a 4-phenylpiperidine derivative and is pharmacologically related to diphenoxylate. Difenoxin acts primarily on peripheral μ-opioid receptors in the gastrointestinal tract, reducing intestinal motility and helping decrease excessive stool frequency.
Difenoxin is identified by CAS No. 2875-85-4. It has the molecular formula C28H34N2O2 and a molecular weight of approximately 430.59 g/mol.
Difenoxin is the principal active metabolite of diphenoxylate and possesses opioid agonist activity. In pharmaceutical use, it has been employed as an antidiarrheal agent, generally in combination with atropine to discourage excessive use and reduce the potential for misuse.
Difenoxin produces its antidiarrheal effect primarily through opioid receptor activity in the gastrointestinal tract. Activation of these receptors decreases intestinal propulsive activity and prolongs intestinal transit time.
Difenoxin acts primarily as a μ-opioid receptor agonist. Activation of opioid receptors in the gastrointestinal tract reduces intestinal smooth-muscle activity and secretory processes, resulting in slower intestinal transit and reduced stool frequency.
Difenoxin has been used in pharmaceutical preparations for:
Approved indications and formulations vary according to country and regulatory requirements.
Difenoxin is relevant to pharmaceutical manufacturers and formulation-development organizations working with gastrointestinal and antidiarrheal pharmaceutical products.
Because Difenoxin has opioid activity, its manufacture, handling, distribution and use may be subject to additional regulatory controls depending on the jurisdiction.
Difenoxin API quality evaluation may include:
Testing should be performed using validated analytical methods appropriate for the API.
Difenoxin intended for pharmaceutical manufacturing should comply with applicable GMP, quality-control and controlled-substance requirements. Regulatory classification can vary by country, so the requirements of the intended market should be verified before commercial handling.
A batch-specific Certificate of Analysis (CoA) should provide relevant analytical results and acceptance criteria.
Difenoxin API should be stored in tightly closed, appropriately labelled packaging under the manufacturer's recommended conditions. Appropriate security, access controls and handling procedures should be maintained where required by applicable regulations.
Difenoxin is relevant to pharmaceutical companies developing or manufacturing antidiarrheal and gastrointestinal formulations, subject to applicable regulatory requirements.
For commercial applications, customers should verify the API form, grade, identity, assay, purity, impurity profile, regulatory status, specification and batch-specific CoA before use.
Consistent Difenoxin API quality is important for reliable formulation development and pharmaceutical manufacturing. Control of identity, assay, purity and related substances supports reproducible product quality.
Appropriate documentation may include a Certificate of Analysis, specification sheet, safety documentation and applicable regulatory information.
| Parameter | Specification |
|---|---|
| Appearance | White to off-white crystalline powder |
| Identification | IR & HPLC compliant |
| Assay (HPLC) | NLT 98.0% by HPLC |
| Loss on Drying | NMT 1.0% |
| Residue on Ignition | NMT 0.5% |
| Heavy Metals | NMT 10 ppm |
| Individual Impurity | NMT 1.0% |
| Water Content | NMT 0.5% |
| Melting Point | 150°C – 154°C |