Drug Calculations Flashcards
(19 cards)
What is the formula to calculate the volume of a liquid medication to give?
Volume = (Required dose ÷ Stock strength) × Stock volume
A patient needs 750 mg of a drug. Stock is 500 mg tablets. How many tablets do you give?
1.5 tablets
How many mg are in 5 mL of a 1% lidocaine solution?
50 mg
A 30 kg child needs 5 mg/kg of a drug. What is the total dose in mg?
150 mg
What is the IV infusion rate (mL/hr) for 1000 mL over 8 hours?
125 mL/hr
Convert 1.5 g to micrograms (mcg).
1
What does ‘BD’ mean on a prescription?
Twice daily
Stock: 125 mg/5 mL. Dose required: 250 mg. How many mL?
10 mL
What should you always check before administering a drug?
Right patient
How many mL are in 1 L?
1000 mL
What is the drop factor formula to calculate IV rate in drops/min?
(Volume × Drop factor) ÷ Time (in minutes)
What is 0.9% sodium chloride in mg/mL?
9 mg/mL
What is the dose if a drug is prescribed at 2 mg/kg and the patient weighs 70 kg?
140 mg
How do you calculate a percentage concentration into mg/mL?
1% = 10 mg/mL
What is the safe maximum single adult dose of paracetamol?
1000 mg (1 g)
How many 250 mg capsules are needed for a 1 g dose?
4 capsules
What does ‘TDS’ mean on a prescription?
Three times daily
What are the 7 rights of medication administration?
Right patient
What is the difference between PGDs and independent prescribing?
PGDs are predefined protocols; independent prescribing allows full clinical decision-making within scope
