<p>May increase plasma concentrations of CYP1A2 substrates (e.g. clozapine, ropinirole, theophylline). Enhances effect of oral anticoagulants (e.g. warfarin) and glibenclamide. Increased toxicity of methotrexate. Plasma concentrations may be increased by probenecid. Reduced absorption with oral multivitamins and mineral supplements containing divalent or trivalent cations (e.g. Fe, Zn, Ca) and antacids containing Al, Ca or Mg. Concomitant use with class IA antiarrhythmics (e.g. quinidine, procainamide), class III antiarrhythmics (e.g. amiodarone, sotalol), TCAs, macrolides and antipsychotics may result in additive effects on QT interval prolongation. Concurrent use with corticosteroids may increase risk of severe tendon disorders. Increased risk of CNS stimulation with NSAIDs. Altered serum concentrations of phenytoin.<br />
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Potentially Fatal: Marked elevation in serum levels of tizanidine which is associated with potentiated hypotensive and sedative effect.<br />
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Thiazides may enhance hyperglycaemia and hypokalaemia caused by corticosteroids. Increased incidence of peptic ulcer or Gl bleeding with concurrent NSAIDs admin. Response to anticoagulants altered. Dose of antidiabetics and antihypertensives needs to be increased. Decreases serum cone of salicylates and antimuscarinic agents. Ethanol may enhance gastric mucosal irritation. Reduced efficacy with concurrent use of carbamazepine, phenytoin, primidone, barbiturates and rifampicin. Mutual inhibition of metabolism between ciclosporin and corticosteroids increase plasma cone of both drugs. Enhanced effect in women taking oestrogens or oral contraceptives.</p>