Phenytoin and indomethicin may reduce effects of frusemide
May provoke severe hypotensive response with ACE  inhibitors
NSAIDs inhibit diuretic and antihypertensive effects

Effects of antihyperetensive drugs are enhanced
Increased incidence of premature beats with cardiac glycosides

Action antogonised by corticosteroids
Diuretic induced volume depletion can potentiate aminoglycoside nephrotoxicity.

Impairs action of hypoglycemic agents
Enhances digitalis toxicity due to hyporkalemia

Volume depletion enhances lithium toxicity
Conversely sudden stopping of diuretic may result in subtherapeutic levels of circulating lithium.

Prolonged paralysis with tubocurarine due to hypokalemia
NSAIDs antogonize hypotensive action.

Suppresses action of oral anticoagulants due to reduced rothrombin activity
Increased risk of hypokalemia when corticosteroids given concurrently

Furosemide may enhance nephrotoxicity co-administered with cephalosporins, and ototoxicity
of aminoglycosides
Amiloride potentiates bone marrow suppression caused by anticancer drugs

Hypertension

Nausea, diarrhoea, blurred vision, dizziness, headache, photosentivity,
hypotension, bone marrow depression,(rare)

hepatic dysfunction, hyperglycemia, glycosuria, ototoxicity,
hyponatremia, idiosyncratic hypersentivity,

dry mouth, fatigue, muscle cramps, nausea, impotence,
raised blood levels of glucose, urates, lipids, calcium,

reduced levels of K and magnesium
raised CPK  levels

fluid and electrolyte imbalance
hypersens

Indication-

Hyperetension

Dosage-

40mg and amiloride 5mg - 1 to 2 tabs daily preferably in the morning