Hydrocortisone: Thiazides may enhance hyperglycaemia and hypokalaemia caused by corticosteroids. Increased incidence of peptic ulcer or GI bleeding with concurrent NSAIDs admin. Response to anticoagulants altered. Dose of antidiabetics and antihypertensives needs to be increased. Decreases serum conc 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 conc of both drugs. Enhanced effect in women taking oestrogens or oral contraceptives. Neomycin: Additive nephrotoxic and neurotoxic effect w/ other aminoglycosides (e.g. paromomycin), bacitracin, cisplatin, vancomycin, amphotericin B,...