The condition and the treatment(s)
Autosomal dominant polycystic kidney disease is an inherited condition that causes cysts (small, fluid‑filled sacs) to grow in the kidneys. Over time these cysts get bigger and affect the way the kidneys work.
Tolvaptan (Jinarc) slows the growth of cysts and helps the kidneys work properly.
NHS Choices (www.nhs.uk) may be a good place to find out more.