Mixing Manufactorers

Whats peoples opinions on the various manufacturers of the same drug, for example I take Mirtazipine, but so far have had two manufacturers, one seemed to work the second not so.

I have had many different manufacturers of Citrolapram and noticed no difference between them.

So is it possible that the quality of the ingredients makes a difference, or does the fact that its made by different manufacturers make no difference.

My reckoning is that chemists must go for the cheapest one, and hence if one manufacturer is cheaper than the other, quality of ingredients must come into play.

Thoughts?

The quality of the ingredients should be identical, so long as you are in a first world country, as the manufacturers are liable to the government to maintain quality control.

While a medication is under patent, the manufacturer which holds the patent can keep the price artificially high. As soon as the patent expires, other manufacturers can bring out less-costly versions under other names. Often the original manufacturer will also bring out its own less-costly version under a different name.

If there is any difference at all, it is usually related to things like how quickly the tablet dissolves, etc. The active ingredient is no different.