I had this condition for 2 years. Came on out of the blue 6years ago. I was given anti inflammatories, acupuncture, physiotherapy, digoxin patches, eccentric heel stretches, ultrasound, kinesthetic taping and sympathy. Eventually after doggedly pestering my Gp I obtained a referral to an orthopaedic consultant who told me to lose weight !!! Soooo helpful. The nurse practitioner at the consultation pulled me to one side, apologised for his behaviour and gave me Achilles tendon supports. They sound like the ones that were described by Grannynannywanny I wore them and this condition cleared up in a week !!
Hope this information helps you because Achilles tendinopathy is very debilitating and you have my utmost sympathy