Storage
Store at room temperature
Synonyms
Prochlorperazine Edisylate Salt; PG20W5VQZS; NSC-757299; DTXSID4074483; 2-Chloro-10-(3-(1-methyl-4-piperazinyl)propyl)phenothiazine edisylate
Molecular Formula
C22H30ClN3O6S3
Smiles
CN1CCN(CC1)CCCN2C3=CC=CC=C3SC4=C2C=C(C=C4)Cl.C(CS(=O)(=O)O)S(=O)(=O)O
Boiling Point
524.8°C at 760 mmHg
General Description
Prochlorperazine edisylate is the edisylate (ethanedisulfonate) salt of a piperazine phenothiazine derivative, which contains a chloro group at the 2-position and a 3-(4-methyl-1-piperazinyl)propyl side chain at the 10-position. The edisylate salt is water-soluble and stable, distinct from the maleate or mesylate salts. The phenothiazine tricyclic ring system is planar, allowing it to interact with dopamine D2 receptors.
Mechanism of Action
Prochlorperazine acts primarily as a dopamine D2 receptor antagonist in the chemoreceptor trigger zone (area postrema) and, at higher doses, in the basal ganglia. This blockade suppresses emesis by preventing dopamine-mediated activation of the vomiting center. It also exhibits weak histamine H1 and muscarinic cholinergic antagonism. The edisylate salt does not alter the pharmacodynamics but provides a stable formulation for parenteral use.
Application
Prochlorperazine is indicated for the control of severe nausea and vomiting, including postoperative, chemotherapy-induced (though less effective than 5-HT3 antagonists), and gastroenteritis-related emesis. It is also used for the symptomatic management of psychotic disorders such as schizophrenia, though it is less potent than haloperidol.
A blinded randomized trial in two emergency departments compared IV hydromorphone (1 mg) with IV prochlorperazine (10 mg) plus diphenhydramine (25 mg) for acute migraine. The trial was stopped early after 127 patients because the prochlorperazine arm was clearly superior: sustained headache relief (mild or none at 2 hours maintained for 48 hours) occurred in 60% of prochlorperazine recipients versus 31% of hydromorphone recipients (difference 28%, NNT 4). The authors conclude that hydromorphone is substantially less effective and should not be used as first‑line therapy for acute migraine in the ED.
Fig. 1 CONSORT flow diagram. (Friedman BW, et al., 2017)
References
- Friedman BW, et al. Randomized study of IV prochlorperazine plus diphenhydramine vs IV hydromorphone for migraine. Neurology. 2017;89(20):2075-2082.
Does Prochlorperazine Edisylate require protection from light during storage?
Yes, it is highly photosensitive. Light exposure causes rapid discoloration (darkening) and degradation. Store in light-resistant, tightly sealed containers, preferably amber glass.
What is the recommended storage temperature for Prochlorperazine Edisylate?
Store at controlled room temperature (15-25°C). Avoid excessive heat above 30°C, which accelerates oxidative degradation of the phenothiazine ring.
Is Prochlorperazine Edisylate stable in solution for injection or oral use?
Aqueous solutions require protection from light and antioxidants (e.g., sodium metabisulfite) for stability.
How is the impurity prochlorperazine sulfoxide (an oxidative degradation product) monitored?
This primary degradation product is specifically quantified using a stability-indicating HPLC method with UV detection, ensuring it remains within USP/EP limits.