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They found an 87 percent increase in discussion of psycho-therapeutic agents on non-moderated health social networks.

Conversely, gastrointestinal agents, hormones, anti-infectives and respiratory agents all increased on moderated health social networks.

There was a 42 percent decrease in discussion of central nervous system agents on health networks that require registration.

Conversely, health social networks that require registration had a 225 percent increase in posts about respiratory agents.

The paper is scheduled to be published in the Journal of Biomedical Informatics.