Prescription
Dr. Muhammad Rashedul Islam
Professor
History
• Prescriptions have been in use
since ancient times
– Latin adopted as standard
language
– “Rx” = prescription
Prescription drug
Drug that requires a prescription because it is
considered potentially harmful if not used under
the supervision of a licensed health care
practitioner
Definition
A prescription is a written, verbal, or electronic
order from a practitioner or designated agent
to a pharmacist for a particular medication for
a specific patient.
Writing Prescriptions
Who can write a Rx?
• Practitioners
– Physicians, veterinarians, dentists
Prescription Formatting
• Heading
• Body
• Closing
Current Prescription Formatting
• Heading
– Name, address, and telephone number of the
prescriber
– Name, sex and age of the patient
– Date of the prescription
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Contents of the Prescription
• Patient Name and Address
– Full first and last name
• Middle initial may be helpful
– DOB – not required, but will be helpful in further
identifying the correct patient to prevent
medication errors
Contents of the Prescription
• Practitioner’s Name, Address, and Phone
number
– Validates prescription
– Provides contact information to clarify any
questions
Contents of the Prescription
• Date
• Date the prescription is issued or written
• Allows the determination of the life of the
prescription to validate refills
• Ensures continual patient supervision
• Promotes patient follow - up
Current Prescription Formatting
• Body
– The Rx symbol
– Name
– dose size or concentration (liquids) of the drug
– Amount to be dispensed
– Directions to the patient
Contents of the Prescription
• Selecting the drug
• Medication Allergies
• Availability
• Cost
Contents of the Prescription
• Name of the drug
– Multiple drugs per prescription can add to
confusion
– KEEP IT SIMPLE
Contents of the Prescription
• Name of the drug - CAUTION:
Look Alike/Sound Alike drug names
• Massive number of new drug releases
• Massive number of reformulations
• Drug marketing strategy
– Build on established names
– New combination drugs – Use converged
names
Contents of the Prescription
• Name of the drug
AVOID THE USE OF:
– Abbreviations
• Many drugs identified with abbreviations
– EX: HCT for hydrochlorothiazide, MSO4 for
morphine sulfate
• Attempts to standardize abbreviations have
been unsuccessful
• Tablets - tab
• Capsule – cap
• Syrup – syr
• Suspension – susp
• Injection – Inj
• Metered dose inhaler – as such
• Lotion – as such
Contents of the Prescription
• Strength of the drug
– Be familiar with drugs and their various dosing
strengths and dosage forms
• When in doubt, use references
Dosing Information
– Weight – based dosing
• Always convert patient weight to correct units (kg)
– Liquid medications
• One product may be available in a number of
concentrations
• Be familiar with various product concentrations
• Indicate BOTH concentration and dose of
medication
• Example: Cephalexin suspension 125 mg/ 5 ml
1 teaspoon/ every 8 h
Contents of the Prescription
• Strength of the drug
– Decimal points
• Avoid trailing zeros.
EX. 5 mg vs. 5.0 mg; can be mistaken for 50
mg
• Always use leading zeros.
EX. 0.8 ml vs. .8 ml; can be mistaken for 8
ml
Contents of the Prescription
• Quantity of the drug
– Prescribe only necessary quantity
– Write for specific quantities rather than time
period (for example: dispense #30 vs. dispense for
1 month)
– Calculate: quantity = frequency per day x
treatment days
– Writing out “Dispense # X” is helpful
Contents of the Prescription
• Directions for use
– Write out in full English or use Latin abbreviations
– Latin abbreviations – more convenient, more
potential for mistakes
• Avoid Dangerous Abbreviations
– Provide clear and specific directions
Directions for use
• Should be clearly indicated
Atenolol 100 mg once daily
Amoxicillin 250 mg t.d.s.
• - Tell the patient what you mean be these times a
day/ four times a day!
Prescription Formatting
• Heading
• Body
• Closing
Current Prescription Formatting
• Closing
–Prescriber’s signature
–Refill instructions
–Generic substitution
instructions
Prescription for controlled drugs must(e.g.morphine)
1. Be completely written in the prescriber’s hand writing
in ink
2. Be signed & dated
3. Carry the prescribers’ address
4. Carry the name & address of the patient
5. State the form of the drug
6. State the total quantity of the drug or the number of
dose units to be disposed in both words & figures
7. State the exact size of each dose in both words &
figure.
Contents of the Prescription
– Date of the order
– Patient Name and Address
– Name of the drug
– Strength of the drug
– Quantity of the drug
– Directions for use
– Practitioner Name, Address, Telephone
number
The Five Rights of
Medicine Administration
1. Right patient
2. Right medicine
3. Right route
4. Right dose
5. Right time
……everytime!
Compatibility and Stability
▪ Instability – modification of the preparation due to storage
conditions resulting in unsuitable product
▪ Incompatibility – two or more products mixed with
resulting preparation unsuitable for administration
▪ Results: product becomes toxic, precipitates or ineffective
▪ Never add medicines to fluid unless compatibility assured
▪ Never mix medicines together unless compatibility
assured
Compatibility and stability
• Heparin / Aminoglycosides
• Hydrocortisone / flucloxacillan
• Co-amoxiclav - stability when reconstituted
Labelling
▪ All products must be labelled fully
▪ Complete label before preparing injection
▪ A record must be kept of all injections prepared and
administered (kardex, infusion chart or both)
▪ Bolus drugs …must be administered immediately on
preparation, do not prepare in advance!
Professional Responsibility
Prescriber and Administrator
▪ Prescription is clear, unambiguous and legal
▪ Medicine is essential and appropriate
▪ Dose, route and rate is essential and appropriate
▪ Medicine is compatible with infusion fluid
▪ Appropriate monitoring requirements are in place
eg ECG machine for potassium infusions
What is an error ?
• Doses omitted • Wrong time of
• Wrong dose administration
• Unprescribed drug – time of day
given – in relation to food
• Wrong dosage form etc....
given • Using unstable/expired
• Wrong route of drug
administration • Wrong administration
• Wrong rate of technique
administration • Incorrect reconstitution
• Extra dose given
Medication Error Prevention…What YOU can do!
HIGH-RISK meds: Be ESPECIALLY cautious!!
INSULINS (continued)
• Dosages: Check and re-check…
• Correct transcription of the insulin brand & dosage?
• Dosages…Is that a “4” or a “9”?...Is that “2U” or “20”?
• Don’t accept orders with “U” instead of “units”!
• Label syringes after drawing up insulin…patient ID, drug name & dose
• Treat one patient at a time…draw up, administer, document…next patient
• Always ask for a double-check
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Examples…
Leading decimal points…lead to errors!!
After receiving an overdose for several weeks, the patient was
admitted to the hospital for hyperthyroidism and weight loss.
The error was recognized during a medical history when the patient
showed a physician the prescription container label.
SAFER!: Lead with 0 when dosage is less than a whole unit, e.g., 0.1
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Examples…
Missing the point entirely!
A line may interfere with the observation of a decimal point. The order for
20.4 mg of Cisplatin (chemotherapy) was interpreted as 204 mg, resulting
in a ten fold overdose and death.
SAFER!...Make sure the decimal point is OBVIOUS!
Examples…
What’s wrong with this picture?
Read the label! Manufacturers often use similarly appearing label
formats on several products (fonts, colors, etc.)
(enalaprilat is for high blood pressure…pancuronium is a paralyzing
agent!!)
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Outpatient Prescription Prescriber’s name license classification
Prescriber’s office (Professional degree)
information Adress
Office telephone numbers
Date
Superscriptio
Patient’s name Date
Patients information Address
n
Superscription
Inscription & Drug name and strength
Subscription Quantity
SIG:
Signatura
REFILL TIMES
OR
UNTIL
NO CHILD PROOF
CONTAINER
WARNING PRESCIBER’S
SIGNATURE
Presciber’s other
identification data
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