Can a simple drug help people with fluid on the brain walk better?

Copied word for word from the study's registry entry, so the wording is the study team's rather than ours.

Inclusion Criteria: 1. Diagnosis of idiopathic normal pressure hydrocephalus according to international guidelines 2. Age ≥ 50 years and ≤ 82 years 3. Cognitive function with Mini-Mental State Examination \> 20 points or cognitive domain of iNPH scale ≥ 30 points. 4. MRI image characteristic of normal pressure hydrocephalus, defined as callosal angle \< 90 degrees and dilated lateral ventricles or pattern of disproportionately enlarged subarachnoid space hydrocephalus (DESH). 5. Signed informed consent form Exclusion Criteria: 1. Exclusion criteria for MRI examination 2. Participation in another medical trial 3. Other disease likely to impact the symptoms of the patient 4. Wheelchair user or unable to walk without support 5. Reduced kidney function with GFR \< 50 6. Reduced liver function (increased INR or alanine transaminase concentrations in plasma elevated more than 1.5 times reference values) 7. Known heart failure 8. Low concentrations of electrolytes in blood plasma that, according to the investigator, prevents participation in the study 9. Angle-closure glaucoma 10. Allergy to acetazolamide, sulfonamides, or sulfonamide derivatives 11. Treatment with phenytoin, valproate, carbamazepine, lithium, oral anticoagulants, thiazide-diuretics, or acetylsalicylic acid \> 100 mg/day 12. Inability to swallow capsules of the same size as the investigational medicinal products (will be tested using empty capsules when the patient is asked to participate in the study) 13. Average walking time for the three walking tests \< 10.5 seconds for men and \< 11.5 seconds for women. 14. Average walking time for the three walking tests \> 50 seconds 15. Inability to comply with the study treatment independently, and a concurrent lack of individuals to help the patient comply with the treatment during the study period 16. Fertile woman without highly effective contraception. A Fertile woman will be tested with pregnancy test before inclusion is possible.