Memantine and stomach

[udinesio]

Hey guys,

I'm taking memantine and getting very upset stomach. I even tried plugging it. While it's not as bad as taking it by mouth, it's still horrible. I was wondering what's the mechanism that leads to this. I read a few pharmacological guides but I don't understand why this happens.

Thanks!

 

[dopamimetic]

Memantine is a potent anti-emetic due to its 5-HT3 antagonism (this mechanism is used to counter chemotherapy-induced vomiting, as well as by the old metoclopramide too). On the other side, it´s a (probably rather potent too) D2 agonist and for some peripheral dopamine agonism makes them very sick. Some doctors even prescribe haloperidol for severe sickness / vomiting (ugh..).

What dose were you using? Starting with the recommended 5mg/d or a higher one? Also, what are you taking it for?

Generally memantine seems to have a huge safety margin. In studies they sometimes started with 60mg at once, and in literature it´s known that one can survive 2g(!) without treatment or damage - just 10 days in dissociative anesthesia ...

Edit: In memantine´s side effects, nausea and vomiting are listed as uncommon, but possible side effects. Maybe you just need to titrate more slowly as the body should adjust. As said, for me it has powerful anti-nausea action.. probably you need to desensibilize the D2 receptors at first.