I know Ginkgo Biloba is known for stimulating blood flow, and is as such, a well known homeopathic supplement within the tinnitus community that helps some, including Coldplay's Chris Martin. Maybe that's what he meant?
Hydrochlorothiazide belongs to a class of drugs known as diuretics/"water pills." It works by causing you to make more urine. This helps your body get rid of extra salt and water. This medication also reduces extra fluid in the body (edema) caused by conditions such as heart failure, liver disease, or kidney disease.