This document discusses the various effects that medications can have on patients. It outlines the main types of effects as therapeutic effects, side effects/adverse effects, toxic effects, idiosyncratic reactions, allergic reactions, drug tolerance, and drug interactions. Therapeutic effects are the intended physiological responses, while side effects are secondary unintended but predictable effects. Adverse effects are more severe unintended responses. Toxic effects occur from prolonged use or impaired metabolism. Idiosyncratic reactions and allergic reactions are unpredictable responses where a patient overreacts or becomes sensitized. Drug tolerance is a reduced reaction from repeated use. Drug interactions occur when two drugs affect each other. Understanding these effects is important for patient education and safety

1. Lt Col Sherly V M
EFFECTS OF MEDICATION

2. INTRODUCTION
• Medications vary considerably in the way they act
and their types of action.
• Patients do not always respond in the same way to
each successive dose of a medication.
• Sometimes the same medication causes very
different responses in different patients
• There fore it is essential to understand all the effects
that medication have on patients

5. TYPES OF MEDICATION ACTION
THERAPEUTIC
EFFECTS
SIDE EFFECTS/
ADVERSE EFFECTS TOXIC EFFECTS
IDIOSYNCRATIC
REACTIONS
ALLERGIC REACTIONS

6. THERAPEUTIC EFFECTS
• The therapeutic effect is the expected or predicted
physiological response that a medication causes..
• Each medication has a desired therapeutic effect
• Some medications have more than one therapeutic effect
• Eg. Prednisolone , a steroid ,decreases swelling, inhibits
inflammation,reduces allergic responses, and prevents
rejection of transplanted organs.
• Knowing the desired therapeutic effect for each medication
allows the nurse to provide patient education and accurately
evaluate its desired effect.

7. SIDE EFFECTS/ADVERSE EFFECTS
• Every medication has a potential to harm a patient.
• Side effects are predictable and often unavoidable secondary
effects produced at a usual therapeutic dose. They are either
harmless or cause injury.
• If the side effects are serious enough to negate the beneficial
effects, the prescriber discontinue the medication.
• Patients often stop taking medications because of side effects.

8. ADVERSE SIDE EFFECTS
• Adverse effects are unintended, undesirable, and often
unpredictable severe responses to medication.
• Some adverse effects are immediate, where as others take
weeks or months to develop.
• When adverse response to medications occur, the prescriber
discontinues the medication immediately

9. TOXIC EFFECTS
• Toxic effects develop after prolonged intake of a medication or
when a medication accumulates in the blood because of
impaired metabolism or excretion.
• Excess amount of medication in the body can cause lethal
effects, depending on its action.
• Eg; toxic level of morphine can cause respiratory depression
and death.
• Antidots are available to treat specific types of medication
toxicity.eg: nalaxone , an opioid antagonist , reverses the
effects of opioid toxicity.

10. IDIOSYNCRATIC REACTIONS
• One of the unpredictable effects in which a patient over reacts
or underreacts to a medication or has a reaction different from
normal. Eg: child who receives diphenhydramine, becomes
extremely agitated or excited instead of drowsy.

11. ALLERGIC REACTIONS
• These are also unpredictable responses to a medication.
• Patient becomes immunologically sensitized to the initial dose
of a medication.
• With repeated administration the patient develops an allergic
response to it, its chemical preservatives, or a metabolite.
• The medication or chemical act as an antigen, triggering the
release of the antibodies in the body.
• Among the different classes antibiotics cause a high incidence
of allergic reactions.

12. ANAPHYLACTIC REACTION
• Anaphylaxis is a serious allergic reaction that is
rapid in onset and may cause death. It typically
causes more than one of the following: an itchy rash,
throat or tongue swelling, shortness of breath,
vomiting, light headedness, and low blood pressure.
These symptoms typically come on over minutes to
hours.

16. • A patient with known history of an allergy to a
medication needs to avoid exposure to that
medication in the future and wear an identification
bracelet, which alert nurses and physicians to the
allergy if the patient is unconscious.

17. DRUG TOLERANCE
• Drug tolerance is a reduced reaction to a drug following its
repeated use.
• Increasing its dosage may re-amplify the drug's effects;
however, this may accelerate tolerance, further reducing the
drug's effects.
• Drug tolerance is indicative of drug use but is not necessarily
associated with drug dependence or addiction.
• The process of tolerance development is reversible (e.g.,
through a drug holiday[6])

18. DRUG INTERACTION
• A drug interaction is a reaction between two (or
more) drugs or between a drug and a food, beverage, or
supplement
• Taking a drug while having certain medical conditions can also
cause a drug interaction.
• A drug interaction can affect how a drug works or cause
unwanted side effects.

20. THANK YOU