As many people have heard me say, if your temperature is over 99.2/99.3, you need to back off on your DNP dosage or even discontinue use. I didn't just come up with this number myself though. This comes from the most extensive human study on DNP to date. In 1937 Simkins studied the effects of DNP on 159 subjects who were kept on DNP for many months to over a year. It's worth noting that he looked at a number of different markers of health, reporting no hepatotoxicity, no renal toxicity, no cardiovascular effects (except for a marked drop in blood pressure in hypertensive patients), no cardiotoxicity, no consistent effect on blood sugar, an improvement in carbohydrate tolerance, negligible effects on the gastro-intestinal tract, and no effect on blood cholesterol.
With respect to body temperature, he explained, "The temperature, pulse rate, and respiration were carefully watched. It was found that the temperature is an excellent guide of impending toxicity. The rule was followed invariably that, when the temperature rose as high as 99.2 F., the drug was either discontinued or the dosage sharply reduced. In this way, many impending reactions were avoided. The temperature usually remained well within the normal limits."
I think that temperature is an excellent yardstick. While a degree may not seem that much, when your temperature starts to rise above the normal range, it means that the heat being produced from uncoupling has started to outstrip your ability to radiate heat. When this happens, your temperature can quickly get out of control, especially as you increase the dosage or even as the same dosage accumulates. Keeping your temperature in the normal range (under 99.2) demonstrates proper thermoreguation. It shows that you're able to safely radiate the increase in heat production.
To answer srch4info, high doses of DNP do NOT always raise your temp near 99.3. There's a great deal of variation in individual response to DNP. While some people can produce a fever with as little as 300mg/day, others can take 600mg/day and still be under 99 degrees. There are a number of different factors involved: people metabolize DNP at different rates, some people are larger than others so that a given dosage is lower relative to their bodyweight, and some people seem better able to radiate heat. All of these factors and more make dosage prescriptions extremely individual with DNP. For this reason, sweeping generalizations for dosing are completely inadequate. Users need to start with a low dosage and slowly increase it until they find the dosage that's right for them, be it 200mg/day or 600mg/day. As a rough, general guideline, though, I'd say 200mg/day is a low dosage, 400mg/day is a moderate dosage, and 600mg/day is a high (read: unsafe) dosage.
To answer litterbox, there's no point of diminishing returns in terms of DNP's ability to increase metabolic rate. It'll keep uncoupling more and more until so much heat is produced that you get hyperthermia and ultimately die. Of course, when organs start to get damaged and proteins start to denature, I think we can agree that your returns are diminishing. We could call death the ultimate diminution in return. Barring toxicity, though, an increase in heat, per se, doesn't appear to diminish DNP's effect at increasing metabolic rate and oxidation of fat.
-Conciliator
