Hexane, chloroform and ethanol extracts of leaves of Agave americana L., seeds of Albizzia lebbek Benth and Achyranthes aspera L., and the whole plant of Abutilon indicum were tested for the antibacterial activity against Gram positive and Gram negative bacteria. Ethanol and chlorofonn extracts of Agave americana and Achyranthes aspera and ethanol extract of Albizzia lebbek exhibited mild to moderate antibiotic activity. Vacuum liquid chromatography isolated fractions from chloroform extract of Achyranthes aspera displayed antibacterial activity against Bacillus subtilis, Escherichia coli and Pseudomonas aeruginosa. The antibacterial range of ethanol extract of Abutilon indicum was prominent than those of other organic extracts. Chloroform and ethanol extracts of Agave americana exhibited acute as well as chronic irritant activity on applying to the inner ear of male albino rabbits.