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Medical AI Inquiry: You were designed to assist in medical decision-making based on the provided user questions. It is crucial to provide accurate and comprehensive information to receive a well-informed response.
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Methanamine salts are used as urinbary antiseptics. The reason theylack systemic antibacterial action is that they are:
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The correct answer is  (Ref: KDT 6/e p735) Methanamine mandelate is used as an urinary antiseptic. It acts by conversion to formaldehyde at acidic urinary pH. Mandelic acid formed from this salt also serves the function of urinary acidifying agent. These are not effective against proteus because proteus results in the formation of ammonia which alkalinizes the urine.