How do thiazides cause hypercalcaemia?

I was discussing with a renal consultant the reasons for avoiding thiazides in patients with sarcoidosis with renal involvement. I think it is well established that they can cause hypercalcaemia but after (not very much) searching on the internet and in textbooks I can't seem to find out why? Does anybody know?

Authored By Amy Huxtable on Sunday 19th January 2014


Tanguy Lafont
Medical Student - St. Georges University, London
Posted almost 7 years ago

Thiazide diuretics act at the distal tubule. They bind onto the Cl- site of an Na+/Cl- co-transporter, inhibiting both the reuptake of Cl and Na. That’s how they achieve their diuretic effect.
Distal tubule cells also have a Na+/Ca2+ antiporter on