Human equivalent dose was about 12mg daily, duration was just 4 days. Cyproheptadine prevented AND reversed soft tissue calcification by acting as an anti-heparin agent, which is similar to what vitamin K2 does.
http://www.ncbi.nlm.nih.gov/pubmed/14324165
"...In the rat, cyproheptadine prevents the soft-tissue calcification elicited by various mast-cell depletors at their subcutaneous injection site. This action does not appear to result from the anti-histaminic anti-serotonin properties of cyproheptadine, which showed in addition an in vitro anti-heparin effect."
http://www.ncbi.nlm.nih.gov/pubmed/14324165
"...In the rat, cyproheptadine prevents the soft-tissue calcification elicited by various mast-cell depletors at their subcutaneous injection site. This action does not appear to result from the anti-histaminic anti-serotonin properties of cyproheptadine, which showed in addition an in vitro anti-heparin effect."