Triprolidine hydrochloride is a first generation antihistamine, histamine H1 antagonist, produced by the reaction of Triprolidine with hydrogen chloride.

The name describes the structure of the molecule:

• Triprolidine refers to triprolidine, an active antihistamine ingredient. Triprolidine is known for its ability to block histamine receptors, thereby reducing allergic symptoms such as sneezing, itching, and nasal congestion.
• hydrochloride indicates that the compound is the salt form of hydrochloric acid. Hydrochlorides are often used in pharmacology to improve the solubility and stability of active ingredients.

Raw Materials and Their Functions

Triprolidine. An organic compound that acts as an antihistamine, blocking histamine receptors in the body.

Hydrochloric Acid. Used to form the hydrochloride salt with triprolidine, enhancing its solubility and stability.

Industrial Chemical Synthesis of Triprolidine Hydrochloride

• Synthesis of Triprolidine through a series of organic chemical reactions involving various intermediates and catalysts.
• Reaction with Hydrochloric Acid. After synthesis, triprolidine is reacted with hydrochloric acid to form triprolidine hydrochloride.
• Reaction Control. The synthesis and hydrochloride formation reactions are monitored to ensure they occur correctly and the final product has the desired pharmaceutical properties.
• Purification. After the reaction, triprolidine hydrochloride is purified to remove impurities and by-products
• Quality Control. The purified triprolidine hydrochloride undergoes quality checks to ensure it meets pharmaceutical standards. After quality control, it is packaged for use in antihistamine medications.

Form and Color

 Triprolidine Hydrochloride is typically a solid in the form of crystalline powder white or slightly yellowish.

What it is used for and where

It is an antihistaminic drug commonly prescribed in clinical practice (1).

Triprolidine hydrochloride studies

Hansen EB Jr, Heflich RH, Korfmacher WA, Miller DW, Cerniglia CE. Microbial transformation of the antihistaminic drug triprolidine hydrochloride. J Pharm Sci. 1988;77(3):259–264. doi:10.1002/jps.2600770316

Simons KJ, Singh M, Gillespie CA, Simons FE. An investigation of the H1-receptor antagonist triprolidine: pharmacokinetics and antihistaminic effects. J Allergy Clin Immunol. 1986;77(2):326–330. doi:10.1016/s0091-6749(86)80112-9

Dev R, Kumar A, Pathak K. Solubility-modulated asymmetric membrane tablets of triprolidine hydrochloride: statistical optimization and evaluation. AAPS PharmSciTech. 2012;13(1):174–183. doi:10.1208/s12249-011-9738-3

Bucke B, Distler HJ, Schoyerer R, Willner W. Rhinitis-Therapie. Erfahrungen mit Triprolidinhydrochlorid/Pseudoephedrinhydrochlorid, einem schleimhautabschwellenden und antiallergisch wirkenden Therapeutikum [Rhinitis therapy. Experiences with triprolidine hydrochloride/pseudoephedrin hydrochloride, a decongestive and antiallergic therapeutic agent]. Fortschr Med. 1983;101(11):494–496.

Febbraro S, Shea T, Cravo AS. Bioavailability of Triprolidine as a Single Agent or in Combination With Pseudoephedrine: A Randomized, Open-Label Crossover Study in Healthy Volunteers [published online ahead of print, 2020 Mar 4]. Clin Pharmacol Drug Dev. 2020;10.1002/cpdd.777.

Molecular Formula: C₁₉H₂₃ClN₂

Molecular  Weight: 314.9 g/mol

CAS: 550-70-9

UNII NG7A104R3J

EC Number: 208-985-0

DSSTox Substance ID: DTXSID10872513

MDL number MFCD00039044  

PubChem Substance ID 24277808

NACRES NA.77

Synonyms: 

• (E)-2-[3-(1-Pyrrolidinyl)-1-p-tolylpropenyl]pyridine hydrochloride
• trans-2-[3-(1-Pyrrolidinyl)-1-p-tolylpropenyl]pyridine hydrochloride
• Actidilat
• Entra
• Venen
• Pyridine, 2-((1E)-1-(4-methylphenyl)-3-(1-pyrrolidinyl)-1-propen-1-yl)-, hydrochloride (1:1)
• Pro-Actidil

References_______________________________________________________

(1) Li S, Liu X, Li L. A Multicenter Retrospective Analysis on Clinical Effectiveness and Economic Assessment of Compound Reserpine and Hydrochlorothiazide Tablets (CRH) for Hypertension. Clinicoecon Outcomes Res. 2020;12:107–114. Published 2020 Feb 12. doi:10.2147/CEOR.S231210