The physicochem. properties and stability of a potential analgesic, N-allyl-N-(3-methoxy-3,3-diphenylpropyl)ammonium chloride (I) [52742-41-3], were determinedThe free base of I, MeOCPh2CH2CH2NHCH2CH:CH2 [52742-40-2] was obtained by treatment of I with 2N NaOH solution and the conductivity of I solutions was measured.The acid degradation products, HOCPh2CH2CH2NHCH2CH:CH2 [94696-70-5], Ph2C:CHCH2NHCH2CH:CH2 [94696-71-6] and Ph2C:CH2 [588-59-0] were identified by spectral data.The compatibility of I with excipients was demonstrated.The storage stability of I at 20° and 50° stored for 14,28 and 56 days was demonstrated.