Types of Medication Action

Question 1

Therapeutic Effects

Answer 1

Expected or predicted physiological response. For example, nitroglycerin reduces cardiac
workload and increases myocardial oxygen supply.

Question 2

Adverse effect: Unintended, undesirable, often unpredictable

Answer 2

Unintended, undesirable, often unpredictable
Patients most at risk for adverse medication
reactions include the very young and older adults, pregnant women,
patients taking multiple medications, patients who are extremely
underweight or overweight, and patients with renal or liver disease.
When adverse responses to medications occur, the health care provider discontinues the medication immediately.

Question 3

Side effect

Answer 3

Predictable, unavoidable secondary effect - most common side effects: anorexia, nausea, vomiting, constipation, drowsiness, and diarrhea.

Question 4

Toxic effect

Answer 4

Accumulation of medication in the bloodstream For example, toxic levels of
morphine, an opioid, cause severe respiratory depression and death.
Antidotes are available to treat specific types of medication toxicity. For
example, naloxone, an opioid antagonist, reverses the effects of opioid
toxicity.

Question 5

Idiosyncratic reaction

Answer 5

Overreaction or underreaction or different reaction from normal For example, a child
who receives diphenhydramine, an antihistamine, becomes extremely
agitated or excited instead of drowsy.

Question 6

Allergic Reactions

Answer 6

Unpredictable response to a medication.The medication
or chemical acts as an antigen, triggering the release of the antibodies in the body. Severe or anaphylactic reactions, which are life threatening, are
characterized by sudden constriction of bronchiolar muscles, edema of the
pharynx and larynx, and severe wheezing and shortness of breath.
Immediate medical attention is required to treat anaphylactic reactions.
Mild allergic reactions: urticaria (hives- raised irregular skin erruptions), rash (small raised vesicles, pruritus (itchy skin), rhinitis (inflammation of mucus membranes in nose)

Question 7

Medication Interactions

Answer 7

One medication modifies the action of another.
When two medications have a synergistic effect, their combined effect is greater than the effect of the
medications when given separately.

Question 8

Medication Tolerance

Answer 8

More medication is required to achieve the same therapeutic effect. Patients hospitalized
for acute illnesses usually do not develop medication tolerance.

Question 9

Medication Dependence

Answer 9

• Physical - physiological adaptation to a medication that manifests by intense
  physical disturbance when the medication is withdrawn
• Psychological - patient desires the
  medication for benefit other than the intended effect