prescription writing prescription handling

Prescription

1. Principles of Prescription Writing
Dr SanjeewaniFonseka
Department of Pharmacology

2. History
Prescriptions have
been in use since
ancient times
Latin adopted as
standard
language
“Rx” =
prescription

3. 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

4. Definition
A prescription is a
written, verbal, or
electronic order
from a practitioner
or designated
agent to a
pharmacistfor a
particular
medication for a
specific patient.

5. Writing Prescriptions
Who can write a Rx?
Practitioners
Physicians, veterinarians, dentists

6. Prescription Formatting
Heading
Body
Closing

7. Current Prescription
Formatting
Heading
Body
Closing

8. Current Prescription
Formatting
Heading
Name, address, and telephone
number of the prescriber
Name, sex and age of the
patient
Date of the prescription
3

9. 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

10. Contents of the Prescription
Practitioner’s Name, Address, and Phone
number
Validates prescription
Provides contact information to clarify
any questions

11. 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

13. Current Prescription
Formatting
Heading
Body
Closing

14. Current Prescription
Formatting
Body
The R
xsymbol
Name
dose size or concentration
(liquids) of the drug
Amount to be dispensed
Directions to the patient
4

15. Contents of the Prescription
Selecting the drug
Medication Allergies
Availability
Cost

16. Contents of the Prescription
Name of the drug
Multiple drugs per prescription can add to
confusion
KEEP IT SIMPLE

17. 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

18. Contents of the Prescription
Name of the drug
AVOID THE USE OF:
Abbreviations
Many drugs identified with
abbreviations
EX: HCTfor hydrochlorothiazide,
MSO4for morphine sulfate
Attempts to standardize abbreviations
have been unsuccessful

19. Abbreviation Potential Problem Preferred Term
U (unit) Mistaken as zero, four Write “unit”
IU (international unit)Mistaken as IV or 10 Write “international unit”
Q.D., Q.O.D. Mistaken for each other.
Period after Q and O after Q
can be mistaken for “I”
Write “daily” and “every
other day”
MS, MSO4, MgSO4 Confused for one another Write “morphine sulfate” or
“magnesium sulfate”
List of dangerous abbreviations, acronyms, and symbols

20. Tablets -tab
Capsule –cap
Syrup –syr
Suspension –susp
Injection –Inj
Metered dose inhaler –as such
Lotion –as such

21. 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

22. Dosing cont;
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: Cephalexinsuspension 125 mg/ 5 ml
1 teaspoon/ every 8 h

23. 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

24. 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

25. Rules for writing quantity of
drug:
Quantities of 1 gram or more should be
written in grams.
Ex -write 2 g.
Quantities less than 1 gram but more than
1 milligram should be written in Milligrams
For eg, write 100 mg, not 0.1 g

26. Quantities less than 1 milligram should be
written in micro / nanogram as
appropriate.
DO NOT abbreviate micro/ nanograms;
since that can lead to Prescribing errors.
For eg. write 100 micrograms, not 0.1 mg,
nor 100 mcg, nor 100 μg
Use ml or mLfor milliliters

27. For some drugs, a maximum dose may need to
be stated ( for eg. ergotamine in migraine &
colchicinein gout).
Eg: Ergotamine 1 mg at onset of attack & repeat
every 30 min if necessary . Do not take more
than 6 mg in one day or more than 12mg in one
week

28. 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

29. Should be clearly indicated
Atenolol100mgonce daily
Amoxicillin 250mgt.d.s.
-Tell the patient what you mean be these
times a day/ four times a day!

31. Contents of the Prescription
Determine preference for brand or generic
product
Brand vs. generic
Is Brand always better? NO
If practitioner prefers brand, must indicate
in print, -do not substitute

32. Sample Prescription-

33. Contents of the Prescription
Indication
Encouraged, seldom practiced
Helps confirm appropriateness of
medication
Reminds patient of drug’s purpose
Facilitates communication between
health care providers

34. Prescription Formatting
Heading
Body
Closing

35. Current Prescription
Formatting
Closing
Prescriber’s signature
Refill instructions
Generic substitution
instructions
5

36. Contents of the Prescription
Refills
To avoid interrupting
maintenance therapy,
practitioners can authorize refills
on a written prescription
Refills authorized are valid only
for life of the prescription –1
year

37. Controlled Substances
Definition -a prescription drug
whose use and distribution is
tightly controlled because of its
abuse potential or risk
Regulation is more strict

38. 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.

39. CASE #1
Poor handwriting contributed to a medication dispensing error
that resulted in a patient with depression receiving the antianxiety
agent Buspar 10 mg instead of Prozac 10 mg

40. CASE #2
A hypertensive patient accidentally received Vantin 200 mg
instead of Vasotec 20 mg when a pharmacist misread this
prescription

41.  SUMMARY

42. MAXIMIZE PATIENT SAFETY
ALWAYS write legibly.
ALWAYS space out words and numbers to
avoid confusion.
ALWAYScomplete medication orders.
AVOID abbreviations.
When in doubt, ask to verify.

43. 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

44. Model Prescription
1)Name: ABC 2)Date:31.07.07
3) Age:70yrs. 4)Sex: male
Diagnosis: Idiopathic Parkinsonism
R
x
9) Tab Levodopa100mg
Tab Carbidopa25mg
2 tablets by mouth 3 times daily for one month .
Take with food.
Dr. SathyaMD
Assistant Prof. Neurology,
Reg. No. 34523