Effects of Medication

Effects of Medication• Side Effects -- unintended or secondary effects• 1. May not be harmful• 2. May permit the drug to be used for a secondary

purpose

• Adverse Effects -- undesired effects that may be harmful

• 1. May damage function of vital organs over prolonged time

• 2. May be minimized by reducing dosage or switching medication

Effects of Medication• Toxic Effects -- can be extremely harmful; can sometimes be life• threatening; implies drug poisoning

• 1. Poison -- any substance which, when ingested, inhaled or absorbed, or when applied to, injected into, or developed within the body, in relatively small amounts, by its chemical action may cause damage to structure or disturbance of function

• 2. Toxin -- a poison; frequently used to refer specifically to a protein produced by some higher plants, certain animals, and pathogenic bacteria, which is highly toxic for other living organisms. Such substances are differentiated from the simple chemical poisons and the vegetable alkaloids by their high molecular weight and antigenicity.

Effects of Medication• Toxicity -- the quality of being poisonous, especially

the degree of virulence of a toxic micron or of a poison

• Drug must be stopped• Additionally may require supportive treatment and

administration of antidotes

Effects of Medication• Causes of Adverse and Toxic Effects---• All drugs are potentially dangerous• 1. Many medications used for everyday illnesses or

chronic diseases are considered harmless, especially if OTC

• 2. OTCs perceived generally to be safe since no prescription is required

• 3. Prescribed medications assumed to be safe since physician would not prescribe something that might harm the patient

• 4. Lack of understanding -- drugs can cause toxicity even if taken as directed

Effects of Medication• Overdose -- taking more than prescribed or advised• 1. Accidentally• 2. Purposeful• Age• 1. Child may be unable to metabolize at needed

rate if dose too large, e.g., parent giving adult dose of Tylenol

• 2. Elderly -- metabolism slows down, organs (liver, kidneys) not working at full capacity – drug levels can build up, eventually leading to toxic levels

Effects of Medication

• Disease• 1. Weakens or impairs function of organs causing

drugs not to be metabolized at efficient rate, potentially leading to toxic buildup

• a. liver – cannot metabolize drugs at most efficient rate

• b. kidneys – cannot excrete substances at most efficient rate

• 2. Some medications cause the organs to be weakened, sometimes to the point of complete failure (may be temporary)

Effects of Medication• Drug Interactions• 1. May react with other drugs creating toxic

substances when combined• 2. May react with another drug potentiating the

effect• 3. Medication may interact with certain foods,

leading to toxic buildup• a. slowing down metabolizing of drug• b. preventing metabolizing of drug• c. combining with drug causing toxic substances to

develop

Effects of Medication• Allergies -- patient’s reactivity is altered due to

previous contact with drug acting as antigen or allergen• 1. Unpredictable• a. may develop after drug has already been taken for

some time• b. may be idiosyncratic; no known reason as to why

patient reacts this way to drug• 2. Not dose-related• 3. Can cause serious toxicity• 4. May be caused by combination with other

substances, intentional or not• 5. Symptoms vary greatly

Effects of Medication• Treatment• A. Overdose and Toxic Effect• 1. Inducing emesis• 2. Gastric lavage• 3. Activated charcoal will absorb some chemicals• 4. In some cases reducing drug levels may be

sufficient, e.g., in gentamycin• 5. Reduce dosage and frequency• 6. Intermittent discontinuation of drug until serum

levels back within normal range

Effects of Medication• Allergies – the drug must be stopped or discontinued

until sensitivity testing is completed• Supportive Treatment• 1. Kidney dialysis in case of renal failure• 2. Administration of antidotes• 3. Mechanical ventilation• 4. Administration of drug-binding agents, e.g., Digibind

for digitalis• Safety• 1. Child resistant containers or caps• 2. Take medication as prescribed• http://learn.genetics.utah.edu/content/addiction/

drugs/mouse.html