
Originally Posted by
ZaLkeN
Here's a little more info I've dug up.
"Test Flu” varies from individual to individual based on their immune system. It’s the intercorelation between your immune system and your endocrine. If you overload one then the other responds unfavorably. It’s your body’s auto immune response to the foreign substance that has entered your body and caused and influx of hormones. Your body sees the large increase as foreign and tries to get rid of it. Triggering an inflammatory response and raising you metabolism. Once your body builds its resistance to it, the symptoms relieve or even resolve. This usually takes a week or so.
“Test Flu” doesn’t necessarily mean your gear is dirty or that it’s good to go either. That’s more of an urban legend than truth.
Generally, the “Test Flu” is far more common with the short ester preparations like propionate. If you are using TestE then maybe consider to change to Test Cyp
A good rule of thumb is the shorter the carboxylic acid chain, then the greater degree of possible tissue irritation that can trigger the auto immune response. The reason being is these esters are acids, so they cause a localized reaction that the body reacts in a common defensive fashion and thus creating the “Test Flu”
Now this not always the case in every person because please remember we are all engineered differently. So everyone reacts differently to different things.