Metoclopramide drug interactions

Potential drug interactions include an increased AUC of zalcitabine when administered in combination with probenecid or cimetidine and decreased bioavailability when zalcitabine is coadministered with antacids or metoclopramide. Lamivudine inhibits the phosphorylation of zalcitabine in vitro, potentially interfering with its efficacy. 

Drug interactions 5-HT3 antagonists are CYP450 substrates. Enzyme inducers (i.e., rifampin, phenytoin) may iixrease S-HTj antagonist clearance, and enzyme inhibitors (i.e, cimetidine, allopurinol) may increase toxichy. Metoclopramide and promethazine are CYP450 substrates. Drug clearance may be altered with concomitant use of enzyme inducers and inhibitors. 

Drugs that may interact with pergolide mesylate include dopamine antagonists, metoclopramide, and drugs known to affect protein binding. 

Drugs that may interact with zalcitabine include antacids, chloramphenicol, cisplatin, dapsone, didanosine, disulfiram, ethionamide, glutethimide, gold, hydralazine, iodoquinol, isoniazid, metronidazole, nitrofurantoin, phenytoin, ribavirin, vincristine, cimetidine, metoclopramide, amphotericin, aminoglycosides, foscarnet, antiretroviral nucleoside analogs, pentamidine, and probenecid. 

Drugs and chemicals are known to cause activated interaction. The depressant action of opioid drugs is enhanced by drugs acting on the central nervous system (CNS) such as alcohol, anesthetics, anxiolytics, hypnotics, tricyclic antidepressants, and antipsychotics. Concomitant administration of opioid analgesics and monoamine oxidase inhibitors (MAOIs) should be avoided, or extra care should be taken if such a therapy is inevitable. Fatal reactions are reported when treated along with selegiline. Interactions also are reported with cyclizine, cimetidine, mexiletine, cisapride, metoclopramide, or domperidone. 

Concomitant administration of paracetamol with other hepatotoxic drugs or drugs acting on liver microsomal enzymes enhances paracetamol toxicity. Other drugs that interact with paracetamol are metoclopramide, probenecid, and cholestyramine.81... 

Incompatibilities of metoclopramide depend on drug concentration, pH, and temperature. It is incompatible with cephalosporins, chloramphenicol, sodium bicarbonate, doxorubicin, cisplatin, and cyclophosphamide. Caution should be exercised with simultaneous administration of metoclopramide with lithium, sym-pathomimetics, antidepressants, bromocriptine, and carbamazepine. Omperazole interacts with tolbutamide, clarithromycin, and phenytoin. Coadministration of rantidine and cisapride increases the plasma concentration of rantidine. Abuse of senna laxative has been reported and may cause hepatitis.176-178... 

Metoclopramide is a first-generation benzamide. The drug acts presynaptically, mainly as a 5-hydroxytryptamine (5-HT serotonin) 5-HT4 receptor agonist and 5-HT3 receptor antagonist but it is also an antagonist at dopamine 1 (Dj) and 2 (D2) receptors (MacDonald 1991). The net effect of the interactions with these receptors is to facilitate acetylcholine release from enteric neurons and promote smooth muscle contrachon. Metoclopramide... 

In a recent study, in silico docking predictions were used to evaluate interactions of 20 commonly used cancer drugs with CYP2D6. The results obtained led to the identification of a new oxidative metabolite of metoclopramide [119,128], The formation of this in silico predicted metabolite was later confirmed by LC-MS following incubation of metoclopramide with HLM and recombinant CYP2D6 [119]. 

Not understood. Studies with human plasma failed to find any evidence that cimetidine in therapeutic concentrations inhibits the metabolism of suxamethonium. However, metoclopramide may do and therefore is possibly the drug responsible for any interaction seen. In vitro studies with very high cimetidine concentrations found inhibition of plasma cholinesterase (pseudocholinesterase) activity. The cimetidine/vecuro-nium interaction is not understood, but it has been suggested that cimetidine may reduce the hepatic metabolism of vecuronium. ... 

Morphine appears to antagonise the effects of metoclopramide on gastric emptying. As a reduction in gastric motility occurs with all opioids they would all be expected to interact with metoclopramide, and other motility stimulants such as domperidone. However, these drugs are commonly used together and the clinical significance of such effects is not clear. Consider also Opioids + Antiemetics Ondansetron , below. 

In 8 healthy subjects a single 10-mg dose of metoclopramide taken 20 minutes before a 600-mg dose of slow-release theophylline (Theo-Dur), caused a small but insignificant 14.5% reduction in the bioavailability of theophylline. However, adverse effects (nausea, headache, tremors, CNS stimulation) were seen more often in those taking metoclopramide than in those taking placebo, possibly because metoclopramide caused an earlier rise in theophylline levels, and because some of the adverse effects of these two drugs may be additive. A later study in 12 healthy subjects found that metoclopramide 15 mg every 6 hours had no effect on the rate or extent of absorption of a 600-mg dose of sustained-release theophylline (Theo-24) A similar lack of interaction was found in another study using Theo-Dur There would seem to be no reason for avoiding eoncurrent use. 

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