What .X stands for
.X is a medical abbreviation for lack of leading zero - written out in full as “Decimal without leading zero (e.g., .5 mg)”. TermDecode files it under dosage abbreviations.
DosageFlagged high riskSourced
Risk
Decimal point may be missed, causing 10-fold overdose
Safer Alternative
Always use leading zero; write "0.5 mg" not ".5 mg"
Seen in context
.5 mg misread as 5 mg
Sources
The risk description and safer alternative above are reproduced from these published lists.
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Other dosage abbreviations
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