Chapter 14 - Lecture

Medication Information

What is medicine?

Substances prescribed for treatment that produce a therapeutically useful effect

What are drugs?

More general term; usually denotes substances used in diagnosis, treatment, or disease prevention

What are the two types of names that a medication can go by?

• Generic names that identify its chemical name 

• Trade names

The FDA is an administration that’s responsible for setting standards on the control of drugs, name the 5 standards used

• Efficacy – effectiveness 

• Purity

• Potency – strength

• Safety

• Toxicity – potential for harm

What are classification systems for drugs?

They vary by country, but they help categorize current and developing drugs, which in turn helps lawmakers, law enforcers, and medical experts understand how best to handle a particular substance

What are the classification systems based off of? (3 things)

• Medical use

• Safety 

• Abuse risk

What is ‘schedule’ in terms of narcotics?

• Classification or separation of drugs based on their potential for abuse or whether they have a current medical use 

• Classed in I, II, III, IV, V

What is a Schedule I narcotic?

Highest level of abuse

What is a Schedule V narcotic?

Drugs with low abuse potential

What are medication properties?

Characteristics that influence how a drug works in the body

What do medication properties help determine?

Helps determine the right drug, dose, and timing

What are the 2 factors that play a role in medical properties?

• Pharmacokinetics

• Pharmacodynamics

What is a dose?

Amount of drug given at one time

What is the route of administration?

How the drug enters the body (oral, injection, topical)

What is pharmacokinetics?

• Study of the way the body processes a drug and includes how drugs are absorbed, reach their site of action, are metabolized and exit the body

• What does the body do to the drug

What are the 4 points of pharmacokinetics?

• Absorption 

• Distribution

• Metabolism

• Excretion

What is absorption?

• How the drug enters the bloodstream 

• Affected by route of administration, food, and pH

What is distribution?

• How the drug spreads through body tissues and fluids

• Influenced by blood flow and protein binding 

What is metabolism?

• How the body breaks down the drug

• Can make drugs more active or prepare them for elimination

What is the main organ in the body that breaks down the drugs?

The liver

What is excretion?

• How the drug leaves the body 

• Liver and lungs also help in this process

What is the main organ that excretes drugs?

Kidneys through urine

What is pharmacodynamics?

• Study of the effects of drugs on the normal physiological functions of the body

• What the drugs do to the body

What are the 5 factors that are included in pharmacodynamics?

• Mechanism of Action

• Therapeutic effect 

• Side effects

• Toxic effects 

• Dose-Response relationship

What is the mechanism of action in pharmacodynamics?

How the drug produces its effect – like binding to a receptor

What is the therapeutic effect in pharmacodynamics?

Desired benefit – like lowering blood pressure

What are side effects in pharmacodynamics?

Unwanted but expected effects – nausea

What are toxic effects in pharmacodynamics?

• Harmful effects from too much of the drug 

• Poisonous, potentially lethal

What is the dose-response relationship in pharmacodynamics?

How different doses affect the body’s response

What are the 6 medication effects?

• Therapeutic effects 

• Side effects 

• Toxic effects 

• Idiosyncratic effects 

• Allergic reactions

• Synergistic effects

What are therapeutic effects in medications?

The intended and desired effects of a medication

What are 3 examples of medications that provide therapeutic effects?

• Pain relief from acetaminophen

• Blood pressure reduction from lisinopril

• Infection control with antibiotics

What are therapeutic effects determined by?

Dose, route, and individual response

What are side effects in medications?

Secondary, often predictable, and unwanted effects

What are 3 examples of medications that cause side effects?

• Nausea from antibiotics

• Drowsiness from antihistamines

• Dry mouth from antidepressants

Are side effects from medications manageable?

May be managed without stopping the drug

What are toxic effects in medications?

Harmful effects caused by excessive dose or prolonged use

What are 3 examples of medications that had toxic effects?

• Liver damage from high doses of acetaminophen

• Kidney damage from long-term NSAID use 

• Respiratory depression from opioid overdose

What are two factors that impact or relate to toxic effects in medications?

Related to dose and drug accumulation

What index helps assess the safety margin of a medication to prevent toxic effects?

Therapeutic Index

What are idiosyncratic effects in medications?

• Unpredictable and rare reactions not related to dose or allergy

• Can be serious and require drug discontinuation

What are 2 examples of medications that have idiosyncratic reactions?

• Genetic reaction causing hemolysis with certain drugs – G6PD deficiency

• Agitation instead of sedation from benzodiazepines

What are two factors that come into play with idiosyncratic reactions?

Due to genetic or unknown factors

What are allergic responses in medications?

• Immune response to a drug due to hypersensitivity to an allergen

• Can range from mild to life-threatening

What are 3 examples of medications that have allergic reactions?

• Rash from penicillin

• Anaphylaxis from contrast dye 

• Hives from sulfa drugs

What are synergistic effects in medications?

• Responses to combined drugs that differ from their individual effects

• Caused by chemical or physiological drug interactions

What are 2 examples of medications that create synergistic effects?

• Alcohol + benzodiazepines = increased sedation

• Acetaminophen + codeine = stronger pain relief

What are two factors that synergistic effects can be?

Therapeutic or dangerous

What is the importance of synergistic effects?

Important in both planning therapy and avoiding harmful combos

What are the 5 reasons that medications are used in radiology?

• As adjunct drugs 

• Enhance imaging – contrast agents 

• Reduce anxiety or pain

• Prevent allergic reactions 

• Manage adverse effects

What are the 6 common categories of medications used in the radiology department?

• Adjunct drugs

• Contrast agents 

• Antihistamines 

• Sedatives 

• Analgesics 

• Emergency medications

What are adjunct medications used for in nuclear medicine?

Used for enhancing imaging quality, reducing organ uptake or motion artifacts, managing patient comfort or physiological responses

What are the 4 common adjunct medications?

• Lugol’s solution – potassium iodide 

• Furosemide – Lasix

• Aminophylline 

• Sincalide – CCK

What is Lugol’s solution or potassium iodide as an adjunct medication?

• Blocks thyroid uptake of radioactive iodine

• Used with I-131 to protect the thyroid 

What is Lasix or furosemide as an adjunct medication?

• Diuretic used in renal scans 

• Promotes urine flow to differentiate obstructive vs. non-obstructive uropathy

What is aminophylline as an adjunct medication?

• Used in myocardial perfusion imaging 

• Reverses effects of adenosine or regadenoson (Lexiscan) in stress tests

What is sincalide (CCK) as an adjunct medication?

• Stimulates the gallbladder to contract for a HIDA scan 

• Helps assess gallbladder ejection fraction

What are antihistamines & steroids for in allergy prevention?

Used for preventing or managing contrast allergies

What are 2 common antihistamines and steroids used in allergy prevention?

• Diphenhydramine or “Benadryl” – antihistamine 

• Prednisone or Methylprednisolone – corticosteroids

What is a common effect of antihistamine medications? What is a common effect of steroid medications?

• Antihistamines – drowsiness 

• Steroids – GI upset 

What are contrast agents?

Used for enhancing visibility of organs, blood vessels, tissues

What are the 2 types of contrast agents?

• Iodinated contrast – CT 

• Gadolinium-based – MRI

What are adverse effects of contrast agents? (2)

• Allergic reactions 

• Nephrotoxicity 

What are some good precautions to do before administering contrast agents?

• Check for allergies 

• Check for kidney function via an eGFR

What are sedatives and anxiolytics in radiology?

Purpose is to relieve anxiety or claustrophobia during procedures

What are 2 common sedatives and anxiolytics?

• Midazolam (Versed) – short-acting 

• Lorazepam (Ativan) – longer-acting for anxious patients 

What are analgesics and pain management medication?

Used for pain relief during or after interventional procedures

What are 3 common analgesics or pain management medications?

• Fentanyl – rapid onset

• Morphine – longer duration 

• Acetaminophen (Tylenol) – mild to moderate pain

What are emergency medications commonly used for?

• Managing severe allergic reactions

• Treating adverse effects of contrast agents 

• Responding to cardiac or respiratory emergencies

What are the 6 common emergency medications?

• Epinephrine

• Diphenhydramine 

• Methylprednisolone 

• Atropine 

• Albuterol 

• Nitroglycerin

What is epinephrine as an emergency medication?

First-line for anaphylaxis – rapidly reverses airway constriction, low blood pressure, and swelling

What is diphenhydramine as an emergency medication?

Antihistamine for mild to moderate allergic reactions – reduces itching, hives, and swelling

What is methylprednisolone as an emergency medication?

Corticosteroid to reduce inflammation and prevent delayed allergic reactions

What is atropine as an emergency medication?

Treats bradycardia – increases the heart rate by blocking parasympathetic stimulation

What is albuterol as an emergency medication?

• Bronchodilator used for wheezing or bronchospasm

• Administered via inhaler or nebulizer

What is nitroglycerin as an emergency medication?

Used for chest pain in suspected cardiac events – causes vasodilation to improve blood flow

What are antimicrobials in radiology?

Drugs used to kill or inhibit the growth of microorganisms – bacteria, viruses, fungi, or parasites

What are anticonvulsants in radiology?

Medications that prevent or reduce the frequency and severity of seizures

What are antiarrhythmics in radiology?

Drugs that help correct or control abnormal heart rhythms – arrhythmias

What are antagonists in radiology?

Substances that block or reduce the effect of another substance, often by binding to a receptor without activating it

What are local anesthetics in radiology?

Medications that temporarily block nerve signals in a specific area to prevent pain during procedures

What are paralytic agents in radiology?

Drugs that temporarily block muscle movement by interfering with nerve signals, often used during surgery or intubation

What are hypoglycemic agents in radiology?

Medications used to lower blood glucose levels in people with diabetes

What are antihypertensives in radiology?

Drugs used to lower and manage high blood pressure – hypertension