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DOSAGE CALCULATION RN FUNDAMENTALS PROCTORED ASSESMENT
Total Questions : 27
Showing 25 questions, Sign in for moreA nurse is preparing to administer phenytoin 200 mg PO to a client. Available is phenytoin oral suspension 125 mg/5 mL. How many mL should the nurse administer? (Round the answer to the nearest whole number. Use a leading zero if it applies. Do not use a trailing zero.)
Explanation
To calculate the dose of phenytoin oral suspension, the nurse should use the following formula:
Dose (mL) = Desired dose (mg) / Concentration (mg/mL) x Volume (mL)
Plugging in the values from the question, we get:
Dose (mL) = 200 mg / 125 mg/5 mL x 5 mL
Simplifying the equation, we get:
Dose (mL) = 8 mL
A nurse is preparing to administer morphine 0.2 mg/kg IM to a child who weighs 77 lb. Available is morphine injection 10 mg/mL. How many mL should the nurse administer? (Round the answer to the nearest tenth. Use a leading zero if it applies. Do not use a trailing zero.)
Explanation
To calculate the dosage of morphine for a child, the nurse needs to convert the child's weight from pounds to kilograms and then multiply it by the prescribed dose per kilogram. The nurse also needs to divide the resulting amount by the concentration of the morphine injection to get the volume to be administered. The formula is:
Volume (mL) = (Weight (kg) x Dose (mg/kg)) / Concentration (mg/mL)
In this case, the child weighs 77 lb, which is equivalent to 35 kg (77 / 2.2 = 35). The prescribed dose is 0.2 mg/kg and the concentration of the morphine injection is 10 mg/mL. Therefore, the volume to be administered is:
Volume (mL) = (35 x 0.2) / 10
Volume (mL) = 0.7
The nurse should round the answer to the nearest tenth, which is 0.7 mL.
A nurse is preparing to administer lorazepam 50 mcg/kg IM to a client who weighs 176 lb. Available is lorazepam 4 mg/mL. How many mL should the nurse administer? (Round the answer to the nearest whole number. Use a leading zero if it applies. Do not use a trailing zero.)
Explanation
This is a question that tests the nurse's ability to calculate drug dosages based on the client's weight and the drug concentration. To solve this problem, the nurse needs to follow these steps:
1. Convert the client's weight from pounds to kilograms by dividing by 2.2. 176 lb / 2.2 = 80 kg.
2. Multiply the client's weight in kilograms by the prescribed dose in micrograms per kilogram to get the total dose in micrograms. 80 kg x 50 mcg/kg = 4000 mcg.
3. Convert the total dose in micrograms to milligrams by dividing by 1000. 4000 mcg / 1000 = 4 mg.
4. Divide the total dose in milligrams by the drug concentration in milligrams per milliliter to get the volume in milliliters. 4 mg / 4 mg/mL = 1 mL.
5. Round the answer to the nearest whole number and add a leading zero if it applies. Do not use a trailing zero. The final answer is 1 mL.
Therefore, the nurse should administer 1 mL of lorazepam IM to the client.
A nurse is preparing to administer diclofenac sodium 200 mg PO daily in equally divided doses every 6 hr. How many mg should the nurse administer per dose? (Round the answer to the nearest whole number. Use a leading zero if it applies. Do not use a trailing zero.)
Explanation
To calculate the dose of diclofenac sodium per administration, the nurse should divide the total daily dose by the number of doses per day.
In this case, the total daily dose is 200 mg and the number of doses per day is 4 (every 6 hr).
Therefore, the dose per administration is 200 mg / 4 = 50 mg.
The nurse should administer 50 mg of diclofenac sodium PO every 6 hr.
A nurse is preparing to administer methylprednisolone acetate 60 mg IM. Available is methylprednisolone acetate injection 80 mg/mL. How many mL should the nurse administer? (Round the answer to the nearest hundredth. Use a leading zero if it applies. Do not use a trailing zero.)
Explanation
To calculate the dose of methylprednisolone acetate injection, the nurse should use the following formula:
Dose (mL) = Desired dose (mg) / Available dose (mg/mL)
Plugging in the values from the question, we get:
Dose (mL) = 60 mg / 80 mg/mL
Dose (mL) = 0.75 mL
A nurse is preparing to administer cefazolin 250 mg IM to a client. Available is cefazolin powder for injection 500 mg vial. The nurse reconstitutes the powder with 2 mL of sterile water for a concentration of 225 mg/mL. How many mL should the nurse administer? (Round the answer to the nearest tenth. Use a leading zero if it applies. Do not use a trailing zero.)
Explanation
To calculate the dosage of cefazolin, the nurse needs to use the formula D/H x Q, where D is the desired dose, H is the dose on hand, and Q is the quantity.
In this case, D is 250 mg, H is 225 mg/mL, and Q is 1 mL.
Plugging these values into the formula, we get:
250 mg / 225 mg/mL x 1 mL = 1.11 mL
Therefore, the nurse should administer 1.1 mL of cefazolin IM to the client.
A nurse on a pediatric unit is implementing a prescription for dexamethasone solution 0.3 mg/kg now. Which of the following additional Information should the nurse have to interpret this prescription and administer this medication? (Select all that apply.)
A nurse is preparing to administer isoniazid 187 mg IM. Available is isoniazid injection 100 mg/mL. How many mL should the nurse administer? (Round the answer to the nearest tenth. Use a leading zero if it applies. Do not use a trailing zero.)
Explanation
To calculate the dosage of isoniazid injection, the nurse should use the formula D/H x Q, where D is the desired dose, H is the dose on hand, and Q is the quantity.
In this case, D is 187 mg, H is 100 mg/mL, and Q is 1 mL.
Plugging these values into the formula, we get:
187 mg / 100 mg/mL x 1 mL = 1.87 mL
To round the answer to the nearest tenth, the final answer is: 1.9 mL
The nurse should administer 1.9 mL of isoniazid injection to the patient.
A nurse is preparing to administer diazepam 10 mg IM stat to a client. Available is diazepam injection 5 mg/mL. How many mL should the nurse administer? (Round the answer to the nearest whole number. Use a leading zero if it applies. Do not use a trailing zero.)
Explanation
To calculate the dosage of diazepam, the nurse needs to use the formula D/H x Q, where D is the desired dose, H is the dose on hand, and Q is the quantity.
In this case, D is 10 mg, H is 5 mg/mL, and Q is 1 mL.
Plugging these values into the formula, we get:
10 mg / 5 mg/mL x 1 mL = 2 mL
Therefore, the nurse should administer 2 mL of diazepam injection to the client.
A nurse is preparing to administer quinapril 20 mg PO Available is quinapril 40 mg tablets. How many tablets should the answer to the nearest tenth Use a leading zero if it applies. Do not use a trailing zero)
Explanation
To calculate the dosage of quinapril, the nurse needs to apply the formula: D/H x Q = X, where D is the desired dose, H is the dose on hand, Q is the quantity of the drug, and X is the amount to administer.
In this case, D = 20 mg, H = 40 mg, Q = 1 tablet, and X is unknown.
Plugging in the values, we get: 20/40 x 1 = X.
Simplifying, we get: 0.5 = X.
Therefore, the nurse should administer 0.5 tablets of quinapril.
A nurse is preparing to reconstitute amoxicillin powder. According to the medication label, how many mL of oral suspension should the nurse expect the bottle to contain following reconstitution? (Round the answer to the nearest whole number. Use a leading zero if it applies. Do not use a trailing zero.)
Explanation
The medication label for amoxicillin powder provides the instructions for reconstituting the oral suspension. The nurse should follow these steps:
- Tap the bottle until all the powder is loose.
- Add about 17 mL of water to the bottle (one-third of the total amount of 51 mL).
- Shake the bottle well to mix the powder and water.
- Add the remaining 34 mL of water to the bottle and shake again.
- Check that the final volume of the oral suspension is 75 mL.
The nurse should expect the bottle to contain 75 mL of oral suspension after reconstitution.
This is because each 5 mL of oral suspension contains 400 mg of amoxicillin, and the net contents of the powder are equivalent to 6 grams (6000 mg) of amoxicillin.
Therefore, 6000 mg / 400 mg = 15, which means that 15 doses of 5 mL each are needed to use up all the powder. Multiplying 15 by 5 mL gives 75 mL, which is the final volume of the oral suspension.
A nurse is caring for a client who has a new prescription for interferon beta-1a 11 mcg subcutaneous three times weekly. Available is interferon beta-1a injection 22 mcg/0.5 mL. How many mL should the nurse administer per dose? (Round the answer to the nearest hundredth. Use a leading zero if it applies. Do not use a trailing zero.)
Explanation
To calculate the dosage of interferon beta-1a for the client, the nurse should use the following formula:
Dose (mL) = Desired dose (mcg) / Available dose (mcg/mL)
Plugging in the values from the prescription and the medication label, we get:
Dose (mL) = 11 mcg / 22 mcg/0.5 mL
Simplifying the fraction, we get:
Dose (mL) = 0.5 / 2
Dividing both sides by 2, we get:
Dose (mL) = 0.25
Therefore, the nurse should administer 0.25 mL of interferon beta-1a per dose.
1A nurse is preparing to administer cetirizine 5 mg PO. Available is cetirizine 2.5 mg/5 mL. How many ml should the nurse administer? (Round the answer to the nearest whole number. Use a leading zero if it applies. Do not use a trailing zero.)
Explanation
To give a patient cetirizine 5 mg PO, the nurse needs to measure the correct amount of liquid medicine. The medicine has a concentration of cetirizine 2.5 mg/5 mL, which means that every 5 mL of liquid contains 2.5 mg of cetirizine.
To find out how many mL of liquid are equivalent to 5 mg of cetirizine, the nurse can use a proportion:
2.5 mg / 5 mL = 5 mg / x mL
Cross-multiplying and solving for x, the nurse gets:
x = (5 mL x 5 mg) / 2.5 mg
x = 10 mL
Therefore, the nurse should administer 10 mL of liquid medicine to give the patient cetirizine 5 mg PO.
A nurse is preparing to administer chlorpromazine 12.5 mg IM to a client. Available is chlorpromazine 25 mg/mL. How many mL should the nurse administer? (Round the answer to the nearest tenth. Use a leading zero if it applies. Do not use a trailing zero.)
Explanation
To calculate the dosage of chlorpromazine for a client, the nurse needs to use the formula D/H x V, where D is the desired dose, H is the dose on hand, and V is the volume on hand.
In this case, D is 12.5 mg, H is 25 mg, and V is 1 mL. Plugging these values into the formula, we get:
12.5 mg / 25 mg x 1 mL = 0.5 mL
The nurse should administer 0.5 mL of chlorpromazine to the client.
A nurse is reviewing a new prescription for alendronate 70 mg PO once per week upon waking to be taken 30 min before food, fluids, or medication with a client who has osteoporosis. The client is to remain upright for 30 min after administration. How should the nurse interpret this prescription for the client?
A nurse is teaching a newly hired nurse about documentation in the medical record. Which of the following abbreviations should the newly hired nurse identify as a metric unit of weight?
A nurse is preparing to administer bumetanide 1.5 mg PO daily. Available is bumetanide 0.5 mg tablets. How many tablets should the nurse administer? (Round the answer to the nearest whole number. Use a leading zero if it applies. Do not use a trailing zero.)
Explanation
To calculate the dosage of bumetanide, the nurse should divide the ordered dose by the available dose and multiply by one tablet.
In this case, the nurse should divide 1.5 mg by 0.5 mg and multiply by one tablet, which gives 3 tablets.
Therefore, the nurse should administer 3 tablets of bumetanide 0.5 mg PO daily.
A nurse is preparing to administer 0.5 g of cefaclor PO to a client. Available is cefaclor 250 mg capsules. How many capsules should the nurse plan to administer? (Round the answer to the nearest whole number. Use a leading zero if it applies. Do not use a trailing zero.)
Explanation
To calculate the number of capsules needed to administer 0.5 g of cefaclor PO, the nurse should use the following formula:
Number of capsules = (Desired dose / Available dose) x 1 capsule
Plugging in the values from the question, we get:
Number of capsules = (0.5 g / 0.25 g) x 1 capsule
Number of capsules = 2 capsules
Therefore, the nurse should plan to administer 2 capsules of cefaclor PO to the client.
A nurse is preparing to administer insulin glargine to a child who has type 1 diabetes mellitus. The client is to receive 10 units subcutaneous once daily at bedtime. Reading the label on the unopened vial, the nurse should determine that the vial contains how many doses of this medication? (Round the answer to the nearest whole number. Use a leading zero if it applies. Do not use a trailing zero.)
Explanation
To determine the number of doses in the vial, we can use the information provided on the label. The vial contains 10 mL of insulin glargine, and each mL has a concentration of 100 units.
Number of units in the vial = Concentration * Volume
Number of units in the vial = 100 units/mL * 10 mL
Number of units in the vial = 1000 units
Therefore, the vial contains 1000 units of insulin glargine. Since the client is to receive 10 units per dose, we can calculate the number of doses:
Number of doses = Total units in the vial / Units per dose
Number of doses = 1000 units / 10 units/dose
Number of doses = 100 doses
So, the vial contains 100 doses of insulin glargine.
A nurse is preparing to administer levothyroxine 5 mcg/kg PO to a client who weighs 220 lb. Available is levothyroxine 75 mcg tablets. How many tablets should the nurse administer? (Round the answer to the nearest whole number. Use a leading zero if it applies. Do not use a trailing zero.)
Explanation
To calculate the dose of levothyroxine for a client who weighs 220 lb, the nurse needs to convert the weight to kilograms first.
One kilogram is equal to 2.2 lb, so the nurse can divide 220 by 2.2 to get 100 kg.
Then, the nurse can multiply the weight in kilograms by the prescribed dose of 1.5 mcg/kg to get 150 mcg.
The nurse can divide this amount by the strength of the available tablets, which is 75 mcg, to get 2 tablets.
Therefore, the nurse should administer 2 tablets of levothyroxine to the client.
A nurse is preparing to administer magnesium hydroxide 2 tbsp PO. How many mL should the nurse administer? (Round the answer to the nearest whole number. Use a leading zero if it applies. Do not use a trailing zero.)
Explanation
The nurse should use the following formula to convert tablespoons to milliliters: 1 tbsp = 15 mL.
Therefore, 2 tbsp = 2 x 15 mL = 30 mL.
The nurse should administer 30 mL of magnesium hydroxide PO.
A nurse is preparing to administer filgrastim 480 mcg subcutaneous daily. Available is filgrastim injection 300 mcg/mL. How many mL should the nurse administer per dose? (Round the answer to the nearest tenth. Use a leading zero if it applies. Do not use a trailing zero.)
Explanation
To calculate the dose of filgrastim, the nurse should use the following formula:
Dose (mL) = Ordered dose (mcg) / Available dose (mcg/mL)
Plugging in the values from the question, we get:
Dose (mL) = 480 mcg / 300 mcg/mL
Dose (mL) = 1.6 mL
A nurse is preparing to administer promethazine 25 mg PO to a client. Available is promethazine 12.5 mg tablets. How many tablets should the nurse administer? (Round the answer to the nearest whole number. Use a leading zero if it applies. Do not use a trailing zero.)
Explanation
To calculate the number of tablets needed to administer promethazine 25 mg PO, the nurse should use the following formula:
(number of tablets) = (desired dose) / (available dose)
Substituting the values given in the question, we get:
(number of tablets) = (25 mg) / (12.5 mg)
Simplifying, we get:
(number of tablets) = 2
Therefore, the nurse should administer 2 tablets of promethazine 12.5 mg to the client.
A nurse is preparing to administer diphenhydramine 35 mg IM. Available is diphenhydramine injection 50 mg/mL. How many mL should the nurse administer? (Round the answer to the nearest tenth. Use a leading zero if it applies. Do not use a trailing zero.)
Explanation
To calculate the dosage of diphenhydramine injection, the nurse should use the formula D/H x Q, where D is the desired dose, H is the dose on hand, and Q is the quantity. In this case, D is 35 mg, H is 50 mg/mL, and Q is 1 mL.
Plugging these values into the formula, we get:
35 mg / 50 mg/mL x 1 mL = 0.7 mL
Therefore, the nurse should administer 0.7 mL of diphenhydramine injection.
A nurse is preparing to administer calcium carbonate 3.9 g PO daily in equally divided doses every 12 hr. Available is calcium carbonate 650 mg tablets. How many tablets should the nurse administer per dose? (Round the answer to the nearest whole number. Use a leading zero if it applies. Do not use a trailing zero.)
Explanation
To calculate the number of tablets that the nurse should administer per dose, the nurse needs to convert the prescribed dose of calcium carbonate from grams to milligrams and then divide it by the strength of the available tablets. The formula is:
Prescribed dose (mg) / Tablet strength (mg) = Number of tablets
The prescribed dose of calcium carbonate is 3.9 g PO daily in equally divided doses every 12 hr.
To convert grams to milligrams, multiply by 1000.
Therefore, 3.9 g = 3900 mg.
Since the doses are equally divided every 12 hr, the nurse needs to divide the daily dose by 2 to get the dose per 12 hr. Therefore, 3900 mg / 2 = 1950 mg.
The available tablets have a strength of 650 mg each.
To find the number of tablets per dose, divide the dose per 12 hr by the tablet strength.
Therefore, 1950 mg / 650 mg = 3 tablets.
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