Synthesized chemotherapeutic substances derived from sulphanilamide (p-aminobenzenesulphonamide) available in a number of forms for parenteral or (commonly) oral dosage. Sulphonamides are bacteriostatically active against a wide variety of Gram-negative and positive bacteria. Many versions of the drug (usually distinguished by the prefix ‘sulpha-’) have been formulated, varying either in their speed of absorption and/or the mode of release of the antimicrobial – portion of the molecule