Treatment of rocky mountain spotted fever, typhus fever & typhus group, Q fever, rickettsial pox & tick fevers caused by Rickettsiae; resp tract infections; lymphogranuloma venereum; psittacosis; trachoma; inclusion conjunctivitis; uncomplicated urethral, endocervical or rectal infections in adult; nongonococcal urethritis; relapsing fever. Treatment of infections caused by gm -ve microorganisms: Chancroid, plague, tularemia, cholera, Campylobacter fetus infections, brucellosis in conjunction w/ streptomycin, bartonellosis, granuloma inguinale. Treatment of infections caused by E. coli, Enterobacter aerogenes, Shigella spp, Acinetobacter spp, resp tract infections caused by H. influenzae; resp tract infections & UTI caused by Klebsiella spp; upper resp tract infections caused by S. pneumoniae; anthrax. Alternative treatment of uncomplicated gonorrhea, syphilis, yaws, listeriosis, Vincent's infection, actinomycosis, infections caused by Clostridium spp. Adjunct to amebicides; severe acne.