Clinical Research Directory

Inclusion Criteria: * Adults between 18 and 70 years (age ≥ 18 years and \<70 years) * Patient with bipolar disorder * Patient treated with lithium for at least 5 years * Patient with a urine concentration defect defined by a maximal urine osmolality \< 600 mOsm/kg * Woman of childbearing age agreeing to use an efficient contraceptive method for 12 months Exclusion Criteria: * Renal failure defined as eGFR \< 30 ml/min/1.73m² estimated by the CKD-EPI equation * Kalemia \> 5 mmol/l * Hypersensitivity or known allergy to amiloride * Hypersensitivity to lactose * Known adrenal insufficiency * Concomitant use of other potassium-sparing treatment (e.g. spironolactone, angiotensin converting enzyme inhibitors (ACE), angiotensin II receptor (AT2R) antagonists, calcineurin inhibitors tacrolimus and ciclosporin) * Acute ongoing infection (less than 3 days before inclusion) * Severe heart failure (NYHA \> II) * Rhythm, conduction or repolarisation disorder present on an ECG done within 12 months prior to inclusion * Acute phase of mood disorder * Uncontrolled diabetes mellitus or diabetes with hyporeninism hypoaldosteronism * Potassium supplements * Use of heparins * Use of trimethoprim * Cirrhosis * Oedemas * Previous use of amiloride use in the 6 months prior to randomisation) * Pregnant or breastfeeding women * Participation in another clinical study involving investigational medicinal product or patient being in the exclusion period at the end of a previous study * Patient refusal to participate * Non-affiliation to a social security regimen or CMU * Patient under State Medical Aid * Subject deprived of freedom, subject under a legal protective measure