This is actually a pretty good instruction on how to spank up a dosage of caffeine powder and I’ve taken these guidelines directly from the Brazilian Caffeine Powder Website called AG-Nutri.Com.br which I am very fond of 
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VARIOUS INSTRUCTIONS:
Please read instructions carefully:
Dosage:
- This is 100% pure and white caffeine powder which is equivalent to pharmaceutical quality!
- This product can be used in very small portions for human consumption, but at own risk.
- Since this product is 100% pure and of the highest available quality it is chemically considered a methylxanthine.
- Methylxanthine products like this caffeine increases performance, concentration, endurance and energy levels in every form + many other mental and physical benefits !!
Mix for human consumption: 
- For better taste mix no more than 200mg of this powerful product in either juice, soda, proteinshakes or similar. The taste is otherwise very bitter!
- Since this caffeine powder has been crystallized and is of high quality you will feel the effect almost immediately or 5 minutes after intake!
Other information:
- This strong caffeine powder is useful for companies that produce their own energydrinks or energyproducts that require high-quality caffeine powder!
- This product, under correct supervision, can be used agains voles, field mice etc., since this caffeine powder can be used to kill them. Some farmers and professionals, use bait that is highly overdosed with caffeine powder to get rid of the voles etc., and it is proven to be highly succesfull.
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source: http://ag-nutri.com.br/buycaffeinepowder.html
