Pylopac

H. pylori infection, Peptic ulcer disease

One strip lansoprazole, 30 mg; clarithromycin, 500 mg; and metronidazole, 500 mg twice daily for 7-14 days

Contraindicated in patients with known severe hypersensitivity to any component. Clarithromycin is contraindicated in patients with a history of cholestatic jaundice/hepatic dysfunction associated with prior use of clarithromycin. Clarithromycin should not be given to patients with history of QT prolongation or ventricular cardiac arrhythmia, including torsades de pointes.

Clarithromycin inhibits protein synthesis by binding to 50s ribosomal subunits of susceptible organisms. It has activity against susceptible streptococci and staphylococci as well as other species including B. catarrhalis, L. spp, C. trachomatis and U. urealyticum. Lansoprazole is a substituted benzimidazole, and is also known as PPI due to its property to block the final step of acid secretion by inhibiting H+/K+ ATPase enzyme system in gastric parietal cell. Both basal and stimulated acid are inhibited. Metronidazole is converted to reduction products that interact w/ DNA to cause destruction of helical DNA structure and strand leading to a protein synthesis inhibition and cell death in susceptible organisms. It is active against most anaerobic protozoa, some gm+ve, gm-ve and facultative anaerobes.

Serious and occasionally fatal hypersensitivity (anaphylactic) reactions have been reported in patients on penicillin therapy, including amoxicillin. Although anaphylaxis is more frequent following parenteral therapy, it has occurred in patients on oral penicillins. These reactions are more likely to occur in individuals with a history of penicillin hypersensitivity and/or a history of sensitivity to multiple allergens.

Adverse reactions which were reported as possibly or probably related to treatment (<3%) in clinical trials when all three components of this therapy were given concomitantly are listed below and divided by body systems. Digestive system : nausea, vomiting, diarrhoea, dark stool, glossitis, oral moniliasis, stomatitis, tongue discoloration, Musculoskeletal System : myalgia, Nervous System : confusion, headache, dizziness, Skin : skin reactions, Urological System : vaginitis, vaginal moniliasis.

Clarithromycin: Reduced efficacy w/ CYP3A inducers (e.g. phenytoin, carbamazepine). Strong inducers of CYP450 system (e.g. efavirenz, rifampicin) may accelerate metabolism, thus lower plasma levels of clarithromycin. Inhibition of metabolism w/ ritonavir. Torsades de pointes may result from concomitant quinidine or disopyramide. Increased phosphodiesterase inhibitor exposure w/ sildenafil, tadalafil or vardenafil. Increased risk of digoxin toxicity. Decreased concentration of zidovudine. Concomitant use w/ atazanavir, itraconazole or saquinavir may result to bi-directional drug interactions. Hypotension, bradyarrhythmias, and lactic acidosis may result when taken w/ verapamil. Increased risk of myopathy, including rhabdomyolysis w/ HMG-CoA reductase inhibitors. Increased risk of hypoglycaemia w/ oral hypoglycaemic drugs (e.g. pioglitazone) and insulin. Risk of serious haemorrhage and elevation of INR and prothrombin time w/ oral anticoagulants. Increased ototoxicity w/ aminoglycosides. Increased and prolonged sedation w/ triabenzodiazepines (e.g. midazolam). Potentially Fatal: Concurrent use w/ ergot alkaloids (e.g. ergotamine or dihydroergotamine) is associated w/ acute ergot toxicity characterised by vasospasm and ischaemia of the extremities. Concomitant use w/ astemizole, cisapride, pimozide and terfenadine may result in QT prolongation or ventricular cardiac arrhythmia. Metronidazole: Concurrent use w/ disulfiram may produce psychotic reactions. May potentiate the effect of oral anticoagulants. May increase risk of lithium toxicity. May reduce the renal clearance resulting to increased toxicity of 5-fluorouracil. May increase serum levels of ciclosporin. May increase plasma levels of busulfan resulting to severe busulfan toxicity. Enhanced metabolism w/ phenobarbital and phenytoin resulting to decreased serum concentrations. Lansoprazole: Increased risk of hypomagnesaemia w/ diuretics and digoxin. May decrease plasma concentration of erlotinib, dasatinib and lapatinib. May decrease the bioavailability of itraconazole and ketoconazole. May increase plasma concentration of cilostazol and methotrexate. Reduced bioavailability w/ antacids and sucralfate. Potentially Fatal: May decrease serum levels and pharmacological effects of rilpivirine and atazanavir.