Is metoprolol tartrate and metoprolol succinate similar?

Metoprolol tartrate and succinate are used for the same purpose, the tartrate being a generic version of Lopressor and succinate being a generic version of Toprol XL.

The active chemical is different, however, so it effects may be somewhat different.

According to wikipedia.org, "the active substance metoprolol is employed either as metoprolol succinate or metoprolol tartrate (whereas 100 mg metoprolol tartrate corresponds to 95 mg metoprolol succinate), respectively as prolonged-release or conventional-release formulation."

I tried both tartrate and succinate, and found a difference in my body reaction. The Tartrate gave me a dry mouth upon awakening in the morning and made my tongue feel a slight tingle. Because I had to take it twice a day, I occasionally forgot to take the second pill. I prefer the Metoprolol Succinate ER. No side effects and conveniently taken once a day. I did experience a difference.