How to work out blood test ratio and conversion

[bubbatetley]

Hi, can someone tell me how to work out my blood test ratio and how the consultants know what dosage to put you on..

Thank you

Bubba

[greygoose]

The consultant doesn't know what dose to put you on, to begin with. He just follows the rules for taking hormones - any hormones: start low and increase slowly.

For levo that means starting on 50 mcg and increasing by 25 mcg every six weeks until your symptoms are all gone. He may not get it quite right but that is the protocol. Unfortunately, a lot of doctors - consultants included - believe that if they get your TSH back somewhere in range, their job is done, no matter how you feel. So, it doesn't always go to plan.

Ratios are for healthy people, not hypos. Hypos need what they need. Some need more than others. And some need higher levels of T3 than T4, so the ratios of a healthy person won't suit most hypos.

To tell how well you convert T4 to T3, if you are on levo only, you need to test the FT4 and the FT3 at the same time, and compare the results. The percentage through the range of the FT4 should be just slightly higher than the percentage of the FT3. To work out percentages, use this converter:

chorobytarczycy.eu/kalkulator

And that's about all I can tell you without more specific details of what you actually want to know.

[bubbatetley in reply to greygoose]

Makes sense SlowDragon, Cheers!!

[greygoose in reply to bubbatetley]

Actually, I'm greygoose.

[bubbatetley in reply to greygoose]

Sorry, Brain fog!!😘

[bubbatetley]

I just wondered how the doctors know what strength of medication one needs

[Gambit62]

the dose depends more on body mass not the test results - but there are a number of other factors that affect how well dosage is absorbed and used.

General protocol is to start on 50mcg (25mcg if there are potential heart issues or person meets certain age criteria) and then increase. There will be blood tests after about 6 weeks to see how you respond to the dose - often just TSH. Unfortunately GPs often just look at the result and don't bother to ask the patient how they are feeling as TSH is quite difficult to use as an isolated measure in gauging the right dose for the patient - the normal range doesn't really apply at that point.