I don't think the brown urine is from metabolites, I think it is from myoglobin. I also don't think the tren cough is from metabolites...
Many people don't get these effects at all, and some people only sometimes get these effects. Also, you can get tren cough almost instantly after injection sometimes. And the brownish/orange urine you can get from other extreme strength-increasing steroids, also only sometimes.
Perhaps some negatives:
1. Tren has a lot of cross receptor activity at the ER and PR and who knows where else.
I mentioned metabolites because of the below (not exactly iron clad evidence, but pretty strong case for metabolites). Can you explain where you got myoglobin? And what muscle injury would cause it? There is so little scientific literature on tren. You'd think with it so widely used in cattle, there would be at least something. There isn't. Anyway, below highlighted in bold:
Rust/brown urine
"Urban wisdom/myth in bodybuilding culture, states that the use of the drug over extended periods of time can lead to kidney damage. The kidney toxicity has not yet been proven, and scientific evidence supporting the idea is suspiciously absent from the bodybuilding community that perpetuates this idea.
The origin of this myth most likely has to do with the rust colored oxidized metabolites of trenbolone which are excreted in urine and often mistaken for blood. After Schänzer (Clin Chem 1996; 42(7): 1001-1020, Metabolism of anabolic androgenic steroids) Trenbolone and 17epi-trenbolone are both excreted (in urine) as conjugates that can be hydrolyzed with beta-glucuronidase. This implies that trenbolone leaves the body as beta-glucuronides or sulfates, that means mostly non metabolized."
Tren cough
"Trenbolone typically requires an intramuscular injection. Consequently, this can cause violent fits of coughing, typically lasting a few seconds. This dry tren cough will diminish after a few seconds (or minutes) following the injection.
Users may also experience a metallic taste in the mouth or/and tightness in the chest. This is a very short-lived side effect and isn’t dangerous. Some bodybuilders have reported this effect happening during roughly 15-20% of injections. Scientists are not sure exactly what causes tren cough, but there are a few theories as to why it occurs.
It is thought that due to the high androgenic activity of this steroid it activates some of the inflammatory lipids called prostaglandins.
They lead to inflammation and vasoconstriction. Vasoconstriction of the muscular wall of the bronchus in the lungs is what triggers this cough reaction. Coughing upon injection can happen with other steroids too, with two popular ones being deca Durabolin and testosterone enanthate. However, trenbolone is more notorious for this side effect.
Some people can experience nausea, because when you’re coughing out the metabolites of trenbolone from your lungs, it can be inhaled back in your body via the nasal cavity. If this experience causes a strong reaction...."
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