Advice & Insight From Pre-Registration Recruitment Exam Specialists
Â
A 54 year old female patient has been admitted onto the ward after receiving a kidney transplant and the consultant would like to estimate creatinine clearance prior to administration of treatment. The patient’s weight is 64kg and he has a serum creatinine of 126 micromol/litre.
Â
You may use the following equation to support you answering this question:
Â
Estimated CrCl (ml/min) = (140 – Age) x Weight x Constant
                                                        Serum creatinine
Â
Where:
Â
Age = years
Weight = kg
Serum creatinine = micromole/litre
Constant = 1.23 for men or 1.04 for women
Â
Answer & Explanation:
Estimated CrCl (ml/min) = (140 – Age) x Weight x Constant
                                                        Serum creatinine
                                          = (140 – 54) x 64 x 1.04
                                                        126
                                          = 45.43ml/min
Â
A drug has an elimination half-life of 14 hours, assuming it is completely absorbed and 1200mg of the drug is administered as the dose, how many mg would you expect to remain in the body after 48 hours? Assume the drug in question has first order pharmacokinetics.
Â
Â
Answer & Explanation:
1200mg starting off and after 14 hours it is halved to 600mg then after another 14 hours halved again to 300mg and after another 14 hours halved again to 150mg but this equals to 42 hours and we need to work out for 48 hours.
Therefore, in the next halve of between 150mg to 75mg in 14 hours the drug is reduced by 75mg so in one hour the drug reduces by 5.36mg and you can then multiply by 6 to work out total drug depletion in 6 hours = 32.14mg.
75mg – 32.14mg = 42.86mg is depleted in 8 hours so you would add this to 75mg to arrive at 117.86mg after 48 hoursÂ
Â
Â
How many litres of a 0.91% stock solution are required to make 2L of a 0.8% solution, using water as the solvent?
Â
Answer & Explanation:
Need to apply formula: C1V1 = C2V2
We know C1 (0.91%) but not V1 and we know C2 (0.8%) and V2 (2L = 2000mls) so simply plug in the known values:
0.91% x V1 = 0.8% x 2000mls
V1 = 0.8% x 2000mls/0.91
V1 = 1758mls/1000 = 1.76 Litres
​
You have been asked to calculate how many milligrams of sodium ions are found in a 200mg tablet of sodium chloride which is required to be used to treat a salt deficiency in a patient. Â
Â
Answer & Explanation:
You would need to know the molecular weight of the two components before starting; Sodium (Na) = 23 and Chloride (Cl) = 35.5
These added together: 23 + 35.5Â = 58.5
​
As you are required to calculate milligrams of sodium:
23/58.5 x 200mg tablet = 78.63mg
Â
Learn the best Pre-Reg Oriel strategies and practice with reflective questions & worked solutions.
Â
​You have been asked to calculate the dose for an antibiotic for a 7 year old child of a drug that is being used unlicensed according to the adult dose. The adult dose is 650mg OD.
You may find the following equation useful:
Â
Dose for child = age (years) x adult dose
                                       Age + 12
Â
Â
Answer & Explanation:
Dose for child = age (years) x adult dose
                                       Age + 12
Dose for child = 7 x 650mgÂ
               7 + 12
= 239.47 mg rounded to 240mg
Â
Â
You receive a prescription for Levetiracetam 100mg/1ml oral syrup for a 5 month old baby weighing 7.2kg. The dose is 7mg/kg once daily, then increased in steps of up to 7mg/kg twice daily (max. per dose 21mg/kg twice daily), dose to be increased every two weeks. Calculate the total quantity you would dispense in mls for a 4 week supply.Â
Â
Â
Answer & Explanation:
7mg per 1kg
50.4mg =x per 7.2kg
100mg in 1ml
50.4mg in x mls = 0.5mls per day
First two weeks: 0.5mls x 14 days = 7mls
Last two weeks: 0.5mls BD x 14 days = 14mls
7ml + 14mls = 21mls
Â
Oriel Pre-Registration Pharmacist Recruitment Numeracy ExamÂ
Oriel Pre-Registration Pharmacist Situational Judgement Test (SJT)​
5 Key Pharmacy Situational Judgement Tips & Techniques
5 Key Pharmacy Numeracy Test Tips & TechniquesÂ
How To Approach Pharmacy Situational Judgement Questions
Free Pre-Registration Pharmacist Recruitment Numeracy Exam Practice Questions
Free Pre-Registration Pharmacist Recruitment Situational Judgement Practice Questions
