Drug classifications

1. Copyright © 2011 F.A. Davis Company
Davis’s Drug Guide for Nurses, 12th Edition
Understanding Drug Understanding Drug
ClassificationsClassifications

2. Davis’s Drug Guide for Nurses, 12th Edition
Copyright © 2011 F.A. Davis Company
Drug ClassificationsDrug Classifications
Drugs can be classified by their therapeutic
use (e.g., antidepressants) or by their
pharmacologic profile (e.g., selective
serotonin reuptake inhibitors).

3. Davis’s Drug Guide for Nurses, 12th Edition
Copyright © 2011 F.A. Davis Company
Drug Classifications (Cont’d)Drug Classifications (Cont’d)
Most texts use a combination of therapeutic and
pharmaceutical classifications
Healthcare workers use both terms when
discussing medications
Other methods of classification are used for
various purposes
For example, the Schedule of Controlled
Substances that classifies drugs by risk for
abuse

4. Davis’s Drug Guide for Nurses, 12th Edition
Copyright © 2011 F.A. Davis Company
Therapeutic ClassificationsTherapeutic Classifications
Therapeutic classes are broad categories based on
therapeutic intent
Antianginals, sedatives, and analgesics are examples of
therapeutic classes
Therapeutic classes include several pharmacologic
classes
The therapeutic class antihypertensives has at least 13
pharmacologic classes

5. Davis’s Drug Guide for Nurses, 12th Edition
Copyright © 2011 F.A. Davis Company
Therapeutic Classifications (Cont’d)Therapeutic Classifications (Cont’d)
Drugs grouped by therapeutic class work in very
different ways
They are not chemically similar
They have different mechanisms of action
Therapeutic class is useful when speaking of
drugs in a general way
“Antihypertensive drugs save lives”
“You will need antihypertensive medication”

6. Davis’s Drug Guide for Nurses, 12th Edition
Copyright © 2011 F.A. Davis Company
Pharmacologic ClassificationsPharmacologic Classifications
Pharmacologic classification is based on
mechanism of action and includes only those
drugs that have the same or similar
mechanism of action
For example, “angiotensin-converting enzyme
inhibitors” (ACE inhibitors) tell you exactly how
the drugs works—they inhibit the enzyme that
converts angiotensin I to angiotensin II

7. Davis’s Drug Guide for Nurses, 12th Edition
Copyright © 2011 F.A. Davis Company
Pharmacologic Classifications (Cont’d)Pharmacologic Classifications (Cont’d)
Pharmacologic classifications describe a drug’s
properties in a specific way
Pharmacologic class is necessary when
determining treatment; a nurse might say
“An ACE inhibitor is more desirable than a beta
blocker”
“Your heart won’t race as much because the
beta blocker prevents beta-adrenergic
receptors in the heart from being stimulated”

8. Davis’s Drug Guide for Nurses, 12th Edition
Copyright © 2011 F.A. Davis Company
Clues to Pharmacologic ClassClues to Pharmacologic Class
Generic names of drugs in the same
pharmacologic class often have the same
suffix
Beta blockers, the pharmacologic class of
medications in the therapeutic class of
antihypertensives, end in “-olol”

9. Copyright © 2011 F.A. Davis Company
Davis’s Drug Guide for Nurses, 12th Edition
Clues to Pharmacologic Class (Cont’d)Clues to Pharmacologic Class (Cont’d)
Pharmacologic Class Identifying Suffix
benzodiazepines “-epam” (e.g., diazepam)
5-HT
3
antagonists “-setron” (e.g., ondansetron)
HMG-CoA reductase
inhibitors
“-statin” (e.g., rosuvastatin)
Monoclonal antibodies “-mab” (e.g., rituximab)

10. Davis’s Drug Guide for Nurses, 12th Edition
Copyright © 2011 F.A. Davis Company
Drugs in a Pharmacologic Class Drugs in a Pharmacologic Class
Have Similar AttributesHave Similar Attributes
Indications
Mechanism of action
Contraindications and precautions
Interactions
Adverse reactions and side effects
These attributes are similar or identical in a pharmacologic
class; if you know about one drug in a class, you will have
some knowledge of other drugs in the class

11. Davis’s Drug Guide for Nurses, 12th Edition
Copyright © 2011 F.A. Davis Company
Drugs in a Pharmacologic Class Drugs in a Pharmacologic Class
May DifferMay Differ
Dosages
Time action profile
Availability

12. Copyright © 2011 F.A. Davis Company
Davis’s Drug Guide for Nurses, 12th Edition
ACE Inhibitors: An Example of a ACE Inhibitors: An Example of a
Pharmacological Class of DrugsPharmacological Class of Drugs
ACE Inhibitors:
Includes at least 10
individual drugs (right)
All end in “-pril”
Commonly prescribed
drugs
benazeprilmoexipril
captoprilperindopril
enalaprilquinapril
fosinoprilramipril
lisinopriltrandolapril

13. Davis’s Drug Guide for Nurses, 12th Edition
Copyright © 2011 F.A. Davis Company
Indication and Action Indication and Action
of ACE Inhibitorsof ACE Inhibitors
IndicationsIndications
Alone or with other agents in the management of
hypertension
ActionsActions
ACE inhibitors block the conversion of angiotensin I
to the vasoconstrictor angiotensin II
ACE inactivates the vasodilator bradykinin and
other vasodilatory prostaglandins
ACE inhibitors increase plasma renin levels and
reduce aldosterone levels; net result: systemic
vasodilation

14. Davis’s Drug Guide for Nurses, 12th Edition
Copyright © 2011 F.A. Davis Company
Therapeutic EffectsTherapeutic Effects
of ACE Inhibitorsof ACE Inhibitors
Lowering of blood pressure in hypertensive
patients
Decreased afterload in patients with CHF
Decreased development of overt heart failure
Increased survival after MI (selected agents
only)
Decreased progression of diabetic
nephropathy (captopril only)

15. Davis’s Drug Guide for Nurses, 12th Edition
Copyright © 2011 F.A. Davis Company
Side Effects ofSide Effects of ACE Inhibitors ACE Inhibitors
CNS: dizziness, fatigue, headache, insomnia, weakness
Resp: cough, eosinophilic pneumonitis
CV: hypotension, angina pectoris, tachycardia
GI: taste disturbances, anorexia, diarrhea, hepatotoxicity (rare),
nausea
GU: proteinuria, impotence, renal failure
Derm: rashes
F and E: hyperkalemia
Hemat: AGRANULOCYTOSIS, NEUTROPENIA (CAPTOPRIL
ONLY)
Misc: ANGIOEDEMA, fever
Note: CAPITALS indicate life-threatening effects; underlines indicate most frequent

16. Davis’s Drug Guide for Nurses, 12th Edition
Copyright © 2011 F.A. Davis Company
Nursing Care oNursing Care of Patients f Patients
on ACE Inhibitorson ACE Inhibitors
Hypertension
Monitor frequency of prescription refills to determine
adherence
Monitor blood pressure and pulse frequently during initial
dose adjustment and periodically during therapy; notify
healthcare professional of significant changes
CHF
Monitor weight and assess patient routinely for resolution
of fluid overload (peripheral edema, rales/crackles,
dyspnea, weight gain, jugular venous distention)

17. Davis’s Drug Guide for Nurses, 12th Edition
Copyright © 2011 F.A. Davis Company
Patient SafetyPatient Safety
Always check other sources if you are uncertain
about a medication’s
Use
Effect
Side effects
Dosage
Route of administration
Monitoring criteria
Any other parameter of safe and responsible medication
administration