From Anti-Anxiety to Anxiety: Explanation of Overdose of Mesembrine

In this report on the effects of mesembrine, the author reports sedation usually from smoking kanna, but is naïve to the concentrated extract.

As well, he has a history of marijuana use and used the extract recreationally.

http://www.erowid.org/experiences/exp.php?ID=68898

Commentary: Initially, mesembrine has SSRI-like effects in low doses. However, large doses may result in serotonin syndrome.

One of the symptom of serotonin syndrome is hypomania which has psychomotor agitation resulting from mental tension and anxiety.

It may be helpful to use a mild sedative such as diphenhydramine (Benadryl) when coming down from a large dose of mesembrine, except where it is counterindicated i.e. mixed drug use.

In that case, it may require a trip to the emergency ward of the local hospital for a strong and fast-acting sedative such as the benzodiazepines i.e. midazolam or the much safer dexmedetomidine (Precedex).

References:

Mesembrine: http://en.wikipedia.org/wiki/Mesembrine
Kanna: http://en.wikipedia.org/wiki/Sceletium_tortuosum
Serotonin syndrome: http://en.wikipedia.org/wiki/Serotonin_syndrome#Signs_and_symptoms
Midazolam: http://en.wikipedia.org/wiki/Midazolam
Dexmedetomidine: http://en.wikipedia.org/wiki/Dexmedetomidine