3.7 Medication Preparation and Administration
Key Takeaways
- Medication preparation requires the three checks: when removing from storage, when preparing, and at the point of administration
- Multi-dose vials must be dated when first opened and discarded after 28 days (or per manufacturer guidelines)
- Reconstitution involves adding a diluent to a powdered medication; follow manufacturer instructions for the correct diluent type and volume
- Insulin types include rapid-acting (lispro, aspart — onset 15 min), short-acting (regular — onset 30 min), intermediate (NPH — onset 1-2 hours), and long-acting (glargine — onset 1-2 hours, 24-hour duration)
- Vaccine administration requires checking the VIS, verifying patient identity and allergies, using the correct route and site, and documenting all required information
- Medication math for the CCMA exam includes basic dosage calculations using the formula: Desired dose ÷ Available dose × Quantity = Amount to administer
Medication administration is one of the most important and commonly tested clinical skills on the CCMA exam. Medical assistants prepare and administer medications under the direction of a licensed provider.
Medication Forms
| Form | Description | Route |
|---|---|---|
| Tablet | Compressed powder; may be scored for splitting | Oral (PO) |
| Capsule | Medication enclosed in a gelatin shell | Oral (PO) |
| Liquid/suspension | Medication in liquid form; shake well before use | Oral (PO) |
| Sublingual tablet | Dissolves under the tongue | Sublingual (SL) |
| Injectable solution | Liquid in a vial or ampule | IM, SubQ, ID, IV |
| Transdermal patch | Absorbed through the skin over time | Topical/transdermal |
| Cream/ointment | Applied to the skin surface | Topical |
| Suppository | Inserted into a body cavity (rectal, vaginal) | Rectal (PR), vaginal |
| Inhaler/nebulizer | Aerosolized medication breathed into lungs | Inhalation |
| Ophthalmic drops | Liquid dropped into the eye | Ophthalmic |
| Otic drops | Liquid dropped into the ear | Otic |
Multi-Dose Vials vs. Single-Dose Vials
| Feature | Multi-Dose Vial | Single-Dose Vial |
|---|---|---|
| Contains | Multiple doses with preservative | One dose; no preservative |
| Dating | Must be dated when first opened | Used immediately; discard remainder |
| Expiration | 28 days after opening (unless manufacturer states otherwise) | Single use; discard after use |
| Contamination risk | Higher (needle enters multiple times) | Lower |
| Best practice | Dedicate to one patient if possible | Preferred for safety |
Reconstitution
Reconstitution is the process of adding a diluent (liquid) to a powdered medication to create a solution for injection:
- Check the manufacturer instructions for diluent type and volume
- Draw up the correct amount of diluent (usually sterile water or normal saline)
- Inject the diluent into the powder vial
- Gently swirl or roll the vial — do NOT shake vigorously (may cause frothing)
- Verify the medication is fully dissolved before withdrawing the dose
- Label the reconstituted vial with: date, time, concentration, your initials, and expiration
- Store per manufacturer instructions (some require refrigeration after reconstitution)
Insulin Types
| Type | Generic Name | Onset | Peak | Duration |
|---|---|---|---|---|
| Rapid-acting | Lispro (Humalog), Aspart (NovoLog) | 10-15 min | 1-2 hours | 3-5 hours |
| Short-acting | Regular (Humulin R, Novolin R) | 30 min | 2-4 hours | 6-8 hours |
| Intermediate | NPH (Humulin N, Novolin N) | 1-2 hours | 4-12 hours | 12-18 hours |
| Long-acting | Glargine (Lantus), Detemir (Levemir) | 1-2 hours | No pronounced peak | 20-24 hours |
| Ultra-long | Degludec (Tresiba) | 1-2 hours | No peak | 42+ hours |
Insulin Administration Tips:
- Administer subcutaneously (SubQ) at 45 or 90 degrees
- Rotate injection sites to prevent lipodystrophy (thickening or thinning of tissue)
- Common sites: abdomen (fastest absorption), outer thigh, upper arm, buttocks
- Do NOT rub the injection site after administration
- When mixing insulin: draw clear (regular/rapid) before cloudy (NPH) — "clear before cloudy"
- Opened insulin vials at room temperature are good for 28 days (check specific product)
Basic Dosage Calculations
Formula: Desired dose ÷ Available dose × Quantity = Amount to administer
D/A × Q = Amount
Example 1: Provider orders 500 mg amoxicillin PO. Available: 250 mg capsules.
- 500 mg ÷ 250 mg × 1 capsule = 2 capsules
Example 2: Provider orders 75 mg of a medication IM. Available: 100 mg/mL.
- 75 mg ÷ 100 mg × 1 mL = 0.75 mL
Example 3: Provider orders 0.5 mg atropine IM. Available: 1 mg/2 mL.
- 0.5 mg ÷ 1 mg × 2 mL = 1 mL
When mixing insulin, which should be drawn into the syringe FIRST?
A provider orders 500 mg of amoxicillin PO. The medication is available as 250 mg capsules. How many capsules should the medical assistant prepare?
A multi-dose vial of medication should be discarded no later than how many days after first opening?
Which type of insulin has the FASTEST onset of action?