Oral Medications¶
Oral medications are the most common route of administration in healthcare. They come in many forms: tablets, capsules, and caplets, and require accurate calculation to ensure the correct dose is given.
Medication Orders¶
Medication orders contain:
| Component | Example |
|---|---|
| Patient name | John Smith |
| Medication name | metoprolol |
| Dose | 25 mg |
| Route | orally (PO) |
| Frequency | twice daily (BID) |
| Prescriber signature | Dr. Jones |
Reading the Stock Label¶
The stock label tells you what is available:
| Component | Example |
|---|---|
| Medication name | metoprolol tartrate |
| Strength | 25 mg per tablet |
| Form | tablet |
| Total quantity | 100 tablets |
Calculating Dosages — Tablets and Capsules¶
Example 1 — whole tablet result: Order: metoprolol 50 mg orally Stock: 25 mg per tablet
Example 2 — partial tablet result: Order: lisinopril 5 mg orally Stock: 10 mg per tablet
Scored vs unscored tablets
- Scored tablets have a line across the middle and are designed to be split — 0.5 tablet is acceptable
- Unscored tablets should never be split
- Enteric coated tablets should never be split or crushed
- Capsules should never be split unless specifically formulated as sprinkle capsules
Example 3 — unit conversion required: Order: levothyroxine 0.1 mg orally Stock: 50 mcg per tablet
Example 4 — higher stock strength: Order: atorvastatin 20 mg orally Stock: 40 mg per tablet
Daily and Multi-Dose Calculations¶
Example 5: Order: metformin 500 mg orally three times daily for 7 days Stock: 500 mg per tablet How many tablets for the full course?
Step 1 — tablets per dose: [500 \cancel{\text{ mg}} \times \frac{1 \text{ tablet}}{500 \cancel{\text{ mg}}} = 1 \text{ tablet per dose}]
Step 2 — total tablets: [1 \text{ tablet} \times 3 \text{ doses/day} \times 7 \text{ days} = 21 \text{ tablets}]
Reasonableness Check¶
Tablet safety guidelines
Verify your setup and consult before administering if:
- Result is more than 3 tablets per dose
- Result is less than 0.5 tablet per dose
- Answer is not a multiple of 0.5
- Never crush or split a medication without verifying it is safe
Practice Problems¶
Problem 1
Order: atenolol 100 mg orally Stock: 50 mg per tablet How many tablets?
Answer
Problem 2
Order: warfarin 2.5 mg orally Stock: 5 mg per tablet How many tablets?
Answer
Verify the tablet is scored before splitting.
Problem 3
Order: levothyroxine 0.075 mg orally Stock: 25 mcg per tablet How many tablets?
Answer
Problem 4
Order: prednisone 40 mg orally Stock: 20 mg per tablet How many tablets?
Answer
Problem 5
Order: amoxicillin 500 mg orally three times daily for 10 days Stock: 250 mg per capsule How many capsules for the full course?
Answer
Step 1 — capsules per dose: [500 \cancel{\text{ mg}} \times \frac{1 \text{ capsule}}{250 \cancel{\text{ mg}}} = 2 \text{ capsules per dose}]
Step 2 — total capsules: [2 \times 3 \times 10 = 60 \text{ capsules}]
Problem 6 — flag this answer
Order: digoxin 0.5 mg orally Stock: 62.5 mcg per tablet How many tablets?
Answer
Flag this
8 tablets is far outside the reasonable range. Verify the order, recheck the stock concentration, and consult the prescriber or pharmacist before administering.
Three-check rule
Read the medication label:
- When retrieving the medication from storage
- When preparing the dose
- Before administering to the patient