Antimicrobial properties of methdilazine and its synergism with antibiotics and some chemotherapeutic agents
Chattopadhyay, D.; Dastidar, S.G.; Chakrabarty, A.N.
Arzneimittel-Forschung 38(7): 869-872
1988
ISSN/ISBN: 0004-4172 PMID: 2905130 Document Number: 306527
The antihistamine methdilazine (Md) was found to possess a significantly high antibacterial action when tested against 367 strains of bacteria belonging to both Gram-positive and gram-negative genera. Diferent groups of bacteriacould be arranged in order of their decreasing sensitivity towards Md as follows: Staphylococcus aureus, V. cholerae, Escherichia coli and Shigella. The range of minimum-inhibitor concentration (.mu.g/ml) varied between25 and 200 in most cases, although few strains wre sensitive even at 10 .mu.g/ml level of Md. 10 different bacteria bacteria sensitive to Md and a number of antibiotics when tested for their interaction with Md on one hand and any of the antibiotics or chemotherapeutic agents on the other, it was found that Md in combination with aminoglycosides and several chemotherapeutics showed enhancementof antibacterial effects resultin in synergism. The chemotherapeutic agents bromodiphenhydramine (Bn), diphenhydramine and methyldopa showed distinct synergism when tested in combination with Md. Determination of the area of inhibition zones for the degree of synergism with Md and streptomycin (Sm) produced statistically significant result (p < 0.01) in comparison with their individual effect. This could also be corroborated by the fractionalinhibitory concentration (FIC) index which was 0.49 for Sm-Md and 0.5 for Bn-Md combinations. The synergism of Sm-Md combination was confirmed by in vivo studies.