Insulin Guanethidine

Concomitant use with anticoagulants may increase plasma levels of both drugs and, after continued therapy, may reduce the plasma levels of anticoagulant effects. Use with chloramphenicol, guanethidine, insulin, monoamine oxidase inhibitors, probenecid, salicylates, or sulfonamides may enhance the hypoglycemic effect by displacing tolazamide from its protein-binding sites. 

Around 40 years ago, the short-lived use of synthalin (II) as a hypoglycaemic drug [2] led to numerous studies on guanidines as potential insulin substitutes [3]. Synthalin itself was withdrawn when it was reported that it can cause liver damage [4], and the widespread interest in guanidines eventually lapsed until the introduction of guanethidine nearly 30 years later. 

INSULIN ADRENERGIC NEURONE BLOCKERS t hypoglycaemic effect Catecholamines are diabetogenic guanethidine blocks the release of catecholamines from nerve endings Monitor blood glucose closely... 

Contraindications to the topical use of hydroxyamphetamine for routine mydriasis are similar to those to phenylephrine. Because of its tachyphylaxis and ineffectiveness in postganglionic denervation, however, hydroxyamphetamine may be a safer mydriatic for use in patients with insulin-dependent diabetes, idiopathic orthostatic hypotension, or chemical sympathectomy produced by therapy with systemic guanethidine, reserpine, or methyl-dopa. Thus hydroxyamphetamine seems to be less strongly contraindicated than phenylephrine for certain high-risk patients. 

Limited evidence su ests that guanethidine has blood glucoselowering activity, which may possibly add to the effects of conventional antidiabetics. One case report su ests soluble insulin may exaggerate the hypotensive effects of debrisoquine. 

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