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This plugin allows you to add a widget to your sidebar or shortcode to a page or post that displays a simple drug half life calculator. The calculator outputs the concentration of the drug that will remain in your system over a period of time. The plugin accepts two values: half-life and dosage. You can find the half life of various drugs and medications at Drugsdb.com.

To see a live example, visit: http://www.drugsdb.com/resources/drug-half-life-calculator/

Use the shortcode [halflife] to display it on posts or pages or add it as a sidebar widget.