Yep that can happen, it will subside after some time. If it gets to unbearable stop running this programs for 24-48hrs and see if the body clear up toxins, try to drink more of good quality water, lemon juice can help depending on situation and resting. But it's totally expected, not always but it is. Just stop the program if it's too much bad. After doing many detoxs the body becomes stronger and this stuff may not happen anymore, less intense and less often. The thing is that this feeling is telling your body is having difficult to excrete the toxins, simply that.
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