BACKGROUND: Most manufacturers of commercially available botulinum toxin A (BTX-A) recommend that the vials should be used within 24 hours after reconstitution to ensure efficacy, which in some instances would mean wastage of remaining reconstituted solution. Several studies have evaluated the efficacy of stored reconstituted BTX-A and have concluded that the use of BTX-A reconstituted and refrigerated for up to 6 weeks prior to administration does not significantly alter its efficacy in the treatment of facial rhytides. OBJECTIVES: Our study aimed to compare the clinical efficacy and safety of freshly reconstituted BTX-A and BTX-A reconstituted 1, 2 or 3 months prior to administration in the treatment of axillary hyperhidrosis. METHODOLOGY: Patients with primary axillary hyperhidrosis were enrolled in this pilot study. Freshly reconstituted BTX-A and BTX-A reconstituted 1, 2 and 3 months prior were administered in 4 pre-determined areas in the same patient. The degree of hyperhidrosis was assessed subjectively using Hyperhidrosis Disease Severity Scale (HDSS) and objectively using Minor’s iodine starch test followed by Sweating Intensity Visual Scale (SIVS) at 0, 2, 6 and 12 weeks after administration. RESULTS: Five patients were enrolled in the study. Kruskall-Wallis test showed that HDSS at baseline was significantly different from follow-up periods with noted improvement from baseline to 2 weeks follow-up. Using Kruskall-Wallis test, SIVS was found to be not significantly different among these 4 treatment areas. In addition, significantly improved SIVS scores were noted as early as 2 weeks after administration in all 4 areas of treatments. There were no noted adverse effects in all patients at baseline and at all follow-up visits. CONCLUSION The clinical efficacy and safety of BTX-A reconstituted 1, 2 and 3 months prior to administration is comparable to that of freshly reconstituted BTX-A in the treatment of axillary hyperhidrosis.