Three middle-aged males and one female were diagnosed as having urinary tract infections (UTIs) between 2001 and 2003 in the Wesley Guild Hospital, Ilesa, a unit of Obafemi Awolowo University Teaching Hospitals Complex, Ile Ife, Osun State, Nigeria. Of the 4 patients, only the female was asymptomatic. The 3 males had Pseudomonas aeruginosa, Klebsiella species, and Staphylococcus aureus, respectively, in their urine samples, while the female had Escherichia coli. All 4 patients were treated with grapefruit seeds (Citrus paradisi) orally for 2 weeks and they all responded satisfactorily to the treatment except the man with P. aeruginosa isolate. However, the initial profuse growth of Pseudomonas isolate in the patient that was resistant to gentamicin, tarivid, and augmentin later subsided to mild growth with reversal of the antibiotic resistance pattern after 2 weeks' treatment with grapefruit seeds. These preliminary data thus suggest an antibacterial characteristic of dried or fresh grapefruit seeds (C. paradisi) when taken at a dosage of 5 to 6 seeds every 8 hours, that is comparable to that of proven antibacterial drugs.