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Benzoic acid / hyoscyamine / methenamine / methylene blue / phenyl salicylate Side Effects

Applies to benzoic acid/hyoscyamine/methenamine/methylene blue/phenyl salicylate: oral tablet


Frequency not reported: Blue to blue-green discoloration of the urine, difficult micturition, acute urinary retention[Ref]


Frequency not reported: Tachycardia, flushing[Ref]


Rare (less than 0.1%): Itching, rash, swelling[Ref]


Frequency not reported: Blue to blue-green discoloration of stools, dry mouth, nausea, vomiting[Ref]

Nervous system

Frequency not reported: Dizziness, drowsiness[Ref]


Rare (less than 0.1%): Allergic reaction (i.e., itching, rash, severe dizziness, swelling, trouble breathing)[Ref]


Rare (less than 0.1%): Dyspnea[Ref]


Frequency not reported: Blurred vision[Ref]


1. "Product Information. Hyophen (benzoic acid/hyoscy/methen/mblue/phenylsal)." BioComp Pharma, San Antonio, TX.

Some side effects of benzoic acid / hyoscyamine / methenamine / methylene blue / phenyl salicylate may not be reported. Always consult your doctor or healthcare specialist for medical advice. You may also report side effects to the FDA.

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