Pharmacology Part II
1. Prescription Writing and DEA Drug Schedules
1.1. Prescription Writing
- You may legally prescribe only those drugs appropriate to your practice (i.e., you may not legally prescribe drugs to treat a vaginal yeast infection).
- Know the patient, patient's history, current medications and disease status. (Don't prescribe as a "favor" for someone.)
- Prescribe only those drugs with which you are familiar. Do not allow the patient to prescribe for you.
- Use the metric system.
- Use generic names unless the prescribed item is a fixed combination.
- Do not abbreviate.
- Write clear and complete instructions in English and in ink. Do not use "as directed."
- Prescribe the correct quantity, e.g., 7-10 day supply for most full-course antibiotic therapies; 2-3 day course of analgesics and/or sedatives.
- Prescribe a reasonable number of refills, including zero (third-party payors may limit the number of refills).
- Prescribe real-world doses, i.e., doses that are both correct and measurable. (It's tough to give half a capsule.)
- Maintain records of what you prescribe.
- Establish a good rapport with the patient and explain how to use the prescribed medication.
- Communicate telephone orders directly and clearly to a pharmacist when telephoning prescriptions.
- Instruct the patient to
- Take the drug as prescribed.
- Read the label on the prescription container.
- Store drugs properly.
- Discard after one year.
- Store controlled substances appropriately and keep necessary records.
- Establish a rapport with a pharmacist and use him/her as an information source.
1.1.1. Elements of a prescription include:
Patient's name, address, and age:
Print clearly where indicated
Date:
State requirements vary, but most prescriptions must be filled within 6 months
Rx (Recipe):
Drug name, strength, and type usually listed as the generic name, and if you specifically want a brand name you must designate "no substitution." Rx is from the Latin for "recipe." List the strength of the product (usually in mg) and the form (e.g., tablets, capsule, suspension, transdermal).
Dispense:
Amount of drug (number of capsules), or time period (1 month supply, etc.)
Refills:
Indicate how many times that drug can be refilled
Substitution:
Can a generic drug be used instead of the one prescribed
1.1.2. Frequently used abbreviations
- T
- one
- PO
- by mouth
- qd
- daily
- PRN
- as needed
- qhs
- every night at bedtime
- q6h
- every six hours
- qid
- four times a day
- Distinction between q6h and qid
- qid and q6h are not the same orders. qid means that the medication is given four times a day while awake (e.g., 8 am, 12 noon, 6 pm, and 10 pm). q6h means that the medication is given four times a day, but by the clock (e.g., 6 am, 12 noon, 6 pm, and 12 midnight).
1.2. DEA Drug Schedules
| Schedule I | Heroin, marijuana |
| No proven therapeutic indication | |
| Significant abuse potential | |
| No FDA approval | |
| Usually used only for research purposes | |
| Schedule II | Narcotics and amphetamines |
| Limited therapeutic indications | |
| High abuse potential | |
| FDA-approved clinical indications | |
| Records: receipt and dispensing at pharmacy and physician's office; need special order forms; need DEA number to prescribe; no refills; emergency telephone orders (prescriptions) only | |
| Schedule III/IV | Opiate-like drugs, e.g., pentazocine, propoxyphene, drug combinations |
| Limited therapeutic applications | |
| Lower, but real abuse potential | |
| FDA-approved indications | |
| Records: Need DEA number to prescribe; maximum of five refills in 6 months | |
| Schedule V | Formerly "exempt narcotics," i.e., Terpin Hydrate and Codeine |
| Codeine-containing cough preparations | |
| Limited abuse potential | |
| Records: Need DEA number; maximum of five refills in 6 months | |
| Laws and regulations vary by state | |
| Schedule VI | Only in Massachusetts |
| All prescription "legend" drugs. Legend refers to the FDA-required statement, "Caution-Federal Law Prohibits Dispensing Without a Prescription" |