Possible Interaction: Clonidine and Niacin

“antagonised the gastroprotective effect of clonidine , it would appear that in the periphery nicotinic , but not muscarinic, cholinergic receptors are likely to be involved in the mucosal protective effect of clonidine.”

“The antiallodynic effect produced by intrathecally administered clonidine was attenuated in a dose-dependent manner by intrathecal treatment with muscarinic and nicotinic antagonists.”

“These data are consistent with the hypothesis that clonidine inhibits nicotinic receptor-induced tyrosine hydroxylase phosphorylation by decreasing calcium influx into chromaffin cells, perhaps by an action at the nicotinic receptor.”

“Only one set of observations has lent support to this suggestion: the rather specific alpha 2-adrenoceptor agonist clonidine inhibits catecholamine secretion evoked by the physiological secretagogue, acetylcholine, and by the related nicotinic agonists, carbachol and nicotine.”

“Both clonidine and noradrenaline reduced the nicotinic fast excitatory postsynaptic potential in a concentration dependent manner, although the maximum effect produced by noradrenaline was greater.”

“This was true for both the hyperpolarization and the conductance increase … causing an elevation in the free intracellular calcium concentration 7 Clonidine … nicotinic fast excitatory postsynaptic potential and the noncholinergic slow excitatory postsynaptic potential 8 All … actions of both were reversed or prevented by phentolamine (100 nM‐1 μM).”

“In pretreated animals the antinicotinic as well as the sympathetic inhibitory actions of clonidine were significantly increased at a dosage of 30 micrograms/kg.”