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Units of Measure

General considerations

• Representation of the units will first be taken from UCUM Standard (The Unified Code for Units of Measure)
• Units are plural when it is grammatically appropriate
• US spelling is preferred over UK spelling. 

For example: Milliliter vs millilitre: milliliter is preferred

• When a number precedes the unit it will take a ‘s’ if greater than 1

For example: Engerix B 20 micrograms per milliliter suspension for injection GlaxoSmithKline Inc. (product)

• If we decided to add a synonym with the unit symbols, the UCUM format (mL) would be preferred  

The FSN format 

The unit is part of the strength information which is found only in FSN 

• Lf (limit of flocculation)
  • The term ‘unit’ is added and will be singular or plural if more than one (1) unit

For example: 2 LF / 0.5 ML vs 2 limit of flocculation units per 0.5 milliliter 

• ELISA units                      
  • Curly braces will not be used

For example: 1440 ELISA Units/mL will become 1440 ELISA units per 0.5 milliliter  

• B
  • In UCUM B = bel but this description does not seem to be appropriate for drug strength
  • It could be translated in ‘billion cells’, but we will not enter this strength in the FSN, because too difficult to express clearly.

For example: Instead of "Vivotif 10 billion cells enteric coated capsule Crucell Switzerland LTD (product)" we will have: "Vivotif enteric coated capsule Crucell Switzerland LTD (product)" 

• ug
  • This is represented by ‘microgram’

For example: FSME-IMMUN 2.4 micrograms per 0.5 milliliter suspension for injection Baxter AG (product) 

•  Plaque forming
  • Curly braces will not be used
  • Exponential number cannot be represented in SNOMED CT 
  • The term ‘unit’ is added and will be singular or plural if more than one (1) unit

For example: Varivax III 1350 plaque forming units powder and diluent for solution for injection Merck Canada Inc. (product)

• 1.0 mL
  • There are inconsistencies using 1.0 mL or /mL
  • UCUM guidelines are followed to be consistent with lab existing content.
  • 1.0 will not be added to the FSN 

For example: Recombivax HB 10 micrograms per milliliter suspension for injection Merck Canada Inc. (product) 

• iU
  • This is represented by ‘International unit’

For example: Imovax Rabies 2.5 international units per milliliter powder for solution for injection Sanofi Pasteur SA (product)

• CCID50
  • In UCUM, defined as : cell culture infectious dose 50% unit
  • The above definition will not be part of the FSN, it will rather be represented as follow:

Strength:  1000000 CCID50 /ML for Rotarix will become: 

Rotarix 1000000 units per milliliter oral suspension GlaxoSmithKline Inc. (product)