I would never use the liquid variety, but only use tablets from a well known manufacturer. Liquids are too risky in that they might be dosed wrong, or you could slip up and give yourself the wrong dose. Many can routinely use 160mcg/day for two weeks cycles and have no long term adverse effects. Dose is different for everyone though. It will cause side effects such as elevated BP and heart rate, so its nothing to be taken lightly. Def not something to use longterm, more than 2 weeks at a time. It loses effectiveness after that long anyhow.