Basic Drug Calculation Practice Problems

1. Ordered: Trilafon 24 mg po bid.
   Available: Trilafon concentrate labeled 16 mg/5 ml.
   How many ml will you administer?      Check your answer
   
                          
   
2. Ordered: SoluMedrol 100 mg IM q8h
   Available: Vial 1 ml in size labeled 125 mg SoluMedrol/3 ml
   How many ml will you administer?
   What size syringe is best to administer this dose? Check your answer
   
                              
   
3. Ordered: Ampicillin 400 mg IM q6h
   Available: Vial with powder.  Label reads: For IM injection, add 3.5 ml diluent (read accompaning circular). Resulting solution contains 250 mg Ampicillin per ml. Use solution within one hour.
   How many ml will you administer?  Check your answer
   
                              
   
4. The physician orders Lasix 20 mg IV stat for a child weighing 34 lbs. The pediatric handbook states that 1 mg/kg is a safe initial dose.  Should you give this dose?     Check your answer
   
                                
   
5. A child with a BSA of 0.32 M² has an order for 25 mg of a drug with an average adult dose of 60 mg.  Calculate the child's dosage. Is the physician's order correct?    Check your answer 
   
                          
   
6. Ordered: Infuse 2 L of Lactated Ringers solution in 24 hours.  The administration set has 12 gtts/ml.  How many gtts/min will you administer the IV?      Check your answer
   
                         
   
7. Ordered: D5W 50 ml with 20 mEq KCl to infuse at 8 mEq KCL/hr per IV pump. How many ml of solution will you administer per hour?   Check your answer
   
                      
   
8. Ordered: Gentamycin 100 mg/100ml IVPB q8h.  The IV handbook states that it should be given over 90 min.  What rate will you set on your IV pump?  Check your answer 

9. Ordered:  Nafcillin 900 mg IVPB q6h for a 27 kg child.   Available:  Dry powder in 1 g vials.   Admin.. set:  60 gtts/ml.  The vial states to reconstitute with 3.4 ml diluent to produce 1g/4 ml with concentration of 250 mg/ml. The medication book recommends giving a concentration of 100 mg/ml, duration of infusion 10-20 minutes.

How many milliliters of the reconstituted medication will you draw up for each dose?    Check your answer   

10.              How much fluid will you need to add to the medication drawn up in question 9 to achieve the recommended concentration?  Check your answer 

11.              What rate (gtts/min) will you infuse the medication in question 9?  Check your answer 

 Review

Sharon Kumm, University of Kansas School of Nursing, October 2006