Cipralex is a refined version of citalopram. If you imagine that cipramil contains approx 50% active ingredient, you will find that cipralex contains 100%. This is becuase the cipramil is based on a steroeisomer, which is a term chemists use to describe a drug with two different forms, that are chemically identical BUT due to their 4 way chemical structures only match one another in a mirror image. Cipramil conatins a 50:50 mix of the two versions. Cipralex conatins 100% of the version allegedely proven to be the effective part. In theory, cipralex is better, as you require half or less of the dosed drug load to achieve the desired results. Both drugs are in the same family and have the same side effect profile, with the key problem being that they make you feel worse for the first 14 days, before they make you feel better.