Drug	Extract of terminology or wording used on ‘Directions for administration’	Correct interpretation	Incorrect interpretation
Vedolizumab (Entyvio®) Entyvio 300mg powder for concentrate for solution for infusion vials	‘Reconstitute with 4.8ml of water for injection… withdraw 5ml of reconstituted solution and add to 250ml of infusion fluid’.	Add 4.8ml to 300mg Entyvio powder and mix. Withdraw 5ml and add it to 250ml infusion fluid.	Add 4.8ml to 300mg Entyvio powder and mix. Withdraw 5ml and add it to 245ml infusion fluid.
Citramag effervescent powder sachets (Citric acid anhydrous 17.79 gram; Magnesium carbonate heavy 11.57 gram)	‘One sachet should be reconstituted with 200ml of hot water; the solution should be allowed to cool for approx. 30 minutes before drinking’.	Measure 200ml of hot water and add one sachet into it and mix.	Add one sachet, add sufficient hot water to produce 200ml of final mixture.
Plenvu® sachets	‘The contents of the single sachet for Dose 1 should be made up to 500ml with water and taken over 30 minutes’.	Add sufficient water to the contents of one sachet to make a final volume of 500ml.	Add 500ml of water to the contents of one sachet.
Vistaprep® oral powder	‘Dissolve the contents of each sachet in 1L water’.	Measure 1L of water, add contents of one sachet into the water.	Add sufficient water to the contents of one sachet and make up to 1L.
Movicol® liquid	‘Dilute 25ml of oral concentrate with 100ml of water’.	Add 100ml of water to 25ml of oral concentrate.	Add 75ml of water to 25ml of concentrate.
Ranitidine 50mg/2ml solution for injection ampoules	‘50mg every 8 hours, dose to be diluted to 20 ml.’	Add 2ml of ranitidine 50mg/2ml injection to 18ml of infusion fluid.	Add 2ml of ranitidine 50mg/2ml injection to 20ml of infusion fluid.
Omeprazole 40mg powder for solution for infusion vials	‘Reconstitute each 40mg vial with infusion fluid and dilute to 100ml with Glucose 5% or Sodium Chloride 0.9%’.	Add sufficient infusion fluid to reconstituted vial until final volume is 100ml.	Add 100ml of infusion fluid to reconstituted infusion vial contents.
Pantoprazole 40mg powder for solution for injection vials	‘Reconstitute 40mg with 10ml sodium chloride 0.9% and dilute with 100ml of infusion fluid’.	Add the contents of the reconstituted vial to 100ml of infusion fluid.	Add sufficient infusion fluid to the contents of the reconstituted vial to make up to 100ml.
Brinavess 500mg/25ml concentrate for solution for infusion vials	‘Dilute to a concentration of 4mg/ml with 100 ml’.	25ml of Brinavess 20mg/ml is added to 100ml of infusion fluid.	25ml of BRINAVESS 20mg/ml is made up to 100ml using infusion fluid.
Clarithromycin 500mg powder for concentrate for solution for infusion vials	‘Dissolve initially in water for injections (500mg in 10ml) then dilute to a concentration of 2mg/ml’.	Inject 10ml of water for injections into a vial containing 500mg, then add sufficient infusion liquid up to 250ml.	Note the manufacturer assumes negligible displacement volume here, otherwise the final concentration would NOT be 500mg/10ml!
Hydrogen Peroxide Solution 3% BP 10 Vols	‘As a mouthwash or gargle dilute one part of the peroxide to two parts of water’.	Add 1 part of peroxide to 2 parts of water so total is 3 parts eg 5ml peroxide + 10ml water, total volume is 15ml.	Add sufficient water to 1 part of peroxide to make a final volume of 2 parts.
Sodium bicarbonate 8.4% (1mmol/ml) solution for injection 10ml ampoules	‘For peripheral infusion, dilute 8.4% solution at least 1 in 10’.	For a 1 in 10 dilution, add 10ml of drug to 90ml of infusion fluid.	Add 10ml of drug to 100ml of infusion fluid.

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