About Clearer: CNS adverse effect burden calculator

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This tool sums frequency of specific adverse effects, or categories of adverse effects, across a list of medications.
The basic premise is that risk for CNS adverse effects is additive - e.g., two medications which both cause confusion, when used in combination, have a greater risk than either individually. In reality, the relationship between drugs is more complex: in some cases AE risk may be multiplicative, either because of the nature of the target or because of drug-drug interactions. Future versions of this tool may integrate PK data, or empirical data regarding drug pairs, for improved precision. Nonetheless, as a quick approximation of the total burden posed by a list of medications, the simplifying assumption of additivity is probably reasonable.

Disclaimer: This tool is not intended to diagnose, treat, cure, or prevent any disease.

For details about the MGH Psychiatry Center for Experimental Drugs and Diagnostics, see

Enter a comma-separated list of FDA medications (either generic or brand names). Select specific adverse effects, or groups of AE's, to determine using the pulldown menu. The calculator then loops through each drug and tabulates the total adverse effect burden based on drug frequencies.
The frequency-parsed adverse effect lists were downloaded from the SIDER site on 11/2/12. The p450 substrate list was derived from the Indiana University School of Medicine web site. The p450 inducer/inhibitor list was derived from BJPharmacol 2011.
Integrating with empirical data drawn from EHR may allow more precise estimate of burden associated with medication pairs.

(c) 2013 Roy Perlis, MD MSc and Massachusetts General Hospital.