Hi, I am 55 years old and was diagnosed with ET about 12 years ago after a routine blood test to find out why I was so tired. I also have restless legs and heavy hands and feet. At the beginning I was visiting hospital every 2 weeks for blood tests. Along the way I have discovered that infection and illness can put my platelet count up and after a serious infection was put on Hydroxy carbamide (for several months). Whilst on this I asked a pharmacist if there was anything I could take to help my energy levels that wouldn't interfere with any medication and he told me Co-Enzyme Q10 as it forms naturally in the body. I did some research and saw that there were reports of it lowering platelets - so, I started taking a 100mg a day and also a high strength garlic capsule (also reported to be good for the blood)  with my Specialists knowledge. Over the years my platelets have come down to normal or just above and visit hospital once a year and have noticed they have risen just after a bout of flu or some other virus. 

Eating healthily and keeping weight down and regular exercise helps too.