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If combined with ranitidine, calcium channel blockers, thyroid treatment, insulin, nicotinic acid, antihistamines, cimetidine, quinine, oral contraceptives, furosemide, isoniazid, phenytoin, oral anabolic steroids, beta-blockers, quinidine, and/or asthma & cold medicine use caution regarding interactions with Metformin.
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Always consult medical resources prior to combining with other medications to gain the most from Metformin therapy. Side-affects induced from pairing could dangerously hinder benefit.
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