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DOSAGE CALCULATION: PN FUNDAMENTALS ONLINE
PRACTICE ASSESSMENT 3.0 REVIEW QUESTIONS WITH
DETAILED VERIFIED ANSWERS
>> Administering phenobarbital 6 mg/kg/day PO divided in equal doses every 12 hrs to a
patient weighing 44 lb. Available 20 mg/5 mL. How many mL per dose?
- correct answer- 15 mL
Patient needs 6 mg per kg a day, in 2 doses that are 12hrs apart & is 44lb; FYI lb/2.2 = x kg
5mL = 20mg SO 1 mL = 4 mg
40lb/2.2 = 20kg so 6mg*20kg = 120mg a day OR 60mg per 12hr dose SO 60mg/4mg= 15mL
>> Administering cefaclor 500 mg PO every 12 hrs. Available cefaclor 250 mg/5 mL. How many
mL per dose?
- correct answer- 10 mL
Patient needs 500mg per dose & 5mL = 250mg SO
10mL = 500mg
>> Administering furosemide 20 mg IM. Available furosemide 10 mg/mL. How many mL for the
injection?
- correct answer- 2 mL
Patient needs 20mg for the injection & 1mL = 10mg SO 2mL = 20mg
>> Administering morphine 4 mg IM. Available is 10 mg/mL. How many mL for the injection?
- correct answer- 0.4 mL
Patient needs 4mg for the injection & 1mL = 10mg SO 0.4mL = 4mg
(Desired*Quantity)/Have = X mL OR (4mg*1mL)/10mg = 0.4mL
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>> Discard suspension how many days after reconstitution?
- correct answer- 14 Days
Discard suspension after 14 days
>> Administering codeine 20 mL oral solution. How many teaspoons (tsp) does this equal?
- correct answer- 4 tsp
FYI 1 tsp = 5 mL so
4 tsp = 20 mL
>> Administering metronidazole 7.5 mg/kg PO. Patient weighs 220 lbs. Available 375
mg/capsule. How many capsules (cap) needed?
- correct answer- 2 cap
Patient needs 7.5mg per kg & is 220lb; FYI lb/2.2 = x kg
220lb/2.2 = 100kg; 7.5mg*100kg = 750mg needed
1cap = 375mg SO 2cap = 750mg
>> Administering famotidine 40 mg PO bedtime. Available 20 mg/tablet. How many tablets (tab)
needed?
- correct answer- 2 tab
Patient needs 40mg & 1tab = 20mg SO 2tab = 40mg
>> Include in the teaching for phenytoin oral suspension:
- correct answer- Store medication in cool area
Label states: -100mg/4mL & total is 4mL
-SHAKE WELL before using
-store below 30 C (86F)
DOSAGE CALCULATION: PN FUNDAMENTALS ONLINE
PRACTICE ASSESSMENT 3.0 REVIEW QUESTIONS WITH
DETAILED VERIFIED ANSWERS
>> Administering phenobarbital 6 mg/kg/day PO divided in equal doses every 12 hrs to a
patient weighing 44 lb. Available 20 mg/5 mL. How many mL per dose?
- correct answer- 15 mL
Patient needs 6 mg per kg a day, in 2 doses that are 12hrs apart & is 44lb; FYI lb/2.2 = x kg
5mL = 20mg SO 1 mL = 4 mg
40lb/2.2 = 20kg so 6mg*20kg = 120mg a day OR 60mg per 12hr dose SO 60mg/4mg= 15mL
>> Administering cefaclor 500 mg PO every 12 hrs. Available cefaclor 250 mg/5 mL. How many
mL per dose?
- correct answer- 10 mL
Patient needs 500mg per dose & 5mL = 250mg SO
10mL = 500mg
>> Administering furosemide 20 mg IM. Available furosemide 10 mg/mL. How many mL for the
injection?
- correct answer- 2 mL
Patient needs 20mg for the injection & 1mL = 10mg SO 2mL = 20mg
>> Administering morphine 4 mg IM. Available is 10 mg/mL. How many mL for the injection?
- correct answer- 0.4 mL
Patient needs 4mg for the injection & 1mL = 10mg SO 0.4mL = 4mg
(Desired*Quantity)/Have = X mL OR (4mg*1mL)/10mg = 0.4mL
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>> Discard suspension how many days after reconstitution?
- correct answer- 14 Days
Discard suspension after 14 days
>> Administering codeine 20 mL oral solution. How many teaspoons (tsp) does this equal?
- correct answer- 4 tsp
FYI 1 tsp = 5 mL so
4 tsp = 20 mL
>> Administering metronidazole 7.5 mg/kg PO. Patient weighs 220 lbs. Available 375
mg/capsule. How many capsules (cap) needed?
- correct answer- 2 cap
Patient needs 7.5mg per kg & is 220lb; FYI lb/2.2 = x kg
220lb/2.2 = 100kg; 7.5mg*100kg = 750mg needed
1cap = 375mg SO 2cap = 750mg
>> Administering famotidine 40 mg PO bedtime. Available 20 mg/tablet. How many tablets (tab)
needed?
- correct answer- 2 tab
Patient needs 40mg & 1tab = 20mg SO 2tab = 40mg
>> Include in the teaching for phenytoin oral suspension:
- correct answer- Store medication in cool area
Label states: -100mg/4mL & total is 4mL
-SHAKE WELL before using
-store below 30 C (86F)
