Pharmacology Overview

Pharmacology Overview

• Definition: The study of drugs, their properties, effects, and mechanisms of action in biological systems.

Key Concepts

1. Pharmacokinetics

   • Absorption: How drugs enter the bloodstream.
   • Distribution: How drugs are transported throughout the body.
   • Metabolism: Chemical alteration of drugs, primarily in the liver.
   • Excretion: Removal of drugs from the body, primarily via kidneys.

2. Pharmacodynamics

   • Mechanism of Action: How a drug produces its effects at the site of action.
   • Receptor Interaction: Drugs may act as agonists (activating receptors) or antagonists (blocking receptors).

3. Drug Classification

   • By Effect: Analgesics (pain relief), antibiotics (infection treatment), antihypertensives (blood pressure control).
   • By Chemical Structure: Compounds with similar chemical properties grouped together.

4. Drug Development

   • Preclinical Testing: Laboratory and animal studies to evaluate safety and efficacy.
   • Clinical Trials: Human subject testing divided into phases (Phase I – IV) to assess safety, dosage, efficacy, and side effects.

5. Dosing and Administration

   • Routes of Administration: Oral, intravenous, intramuscular, topical, etc.
   • Dosing Regimens: Specific schedules for drug administration (e.g., once daily, twice a day).

6. Adverse Effects

   • Side Effects: Unintended reactions, can be mild or severe.
   • Drug Interactions: Effects caused by the concurrent use of multiple drugs.

7. Therapeutic Drug Monitoring

   • Important for drugs with narrow therapeutic indices to ensure levels remain within the therapeutic range.

8. Regulatory Factors

   • Agencies govern drug approval and monitoring (e.g., FDA in the U.S.).
   • Importance of adherence to guidelines and protocols in drug development.

Important Terms

• Bioavailability: The proportion of a drug that enters circulation when introduced into the body.
• Half-life: Time taken for the concentration of a drug in the bloodstream to reduce by half.
• Tolerance: Reduced response to a drug after prolonged use.
• Dependence: Physical or psychological need for a drug, leading to withdrawal symptoms upon discontinuation.

Special Considerations

• Patient Variability: Factors such as age, weight, genetics, and existing health conditions can affect drug response.
• Ethical Issues: Informed consent, access to medication, off-label drug use.

Pharmacology Overview

• The study of drugs, their characteristics, effects, and how they work in living organisms.

Pharmacokinetics

• Absorption: The process of a drug entering the bloodstream.
• Distribution: How a drug travels throughout the body.
• Metabolism: Chemical changes to a drug, mainly in the liver.
• Excretion: Removal of drugs from the body, primarily through the kidneys.

Pharmacodynamics

• Mechanism of Action: How a drug produces its effects at the target site.
• Receptor Interaction: Drugs can act as agonists, activating receptors, or antagonists, blocking receptors.

Drug Classification

• By Effect: Grouping drugs based on their therapeutic actions, like pain relief (analgesics), infection treatment (antibiotics), or blood pressure control (antihypertensives).
• By Chemical Structure: Grouping drugs with similar chemical properties.

Drug Development

• Preclinical Testing: Lab and animal studies to assess safety and effectiveness.
• Clinical Trials: Human testing in phases (Phase I – IV) to evaluate safety, dosage, effectiveness, and side effects.

Dosing and Administration

• Routes of Administration: Different ways to give drugs, such as oral, intravenous, intramuscular, or topical.
• Dosing Regimens: Specific schedules for drug administration, like once a day or twice a day.

Adverse Effects

• Side Effects: Unwanted reactions, ranging from mild to severe.
• Drug Interactions: Effects caused by using multiple drugs together.

Therapeutic Drug Monitoring

• Important for drugs with a narrow therapeutic range, ensuring levels stay within the effective range.

Regulatory Factors

• Agencies like the FDA (in the U.S.) oversee drug approval and monitoring.
• Following guidelines and protocols is crucial in drug development.

Important Terms

• Bioavailability: The amount of a drug that reaches circulation after administration.
• Half-life: The time it takes for a drug's blood concentration to decrease by half.
• Tolerance: Decreased response to a drug after prolonged use.
• Dependence: Physical or psychological need for a drug, causing withdrawal symptoms when stopped.

Special Considerations

• Patient Variability: Factors like age, weight, genetics, and health conditions affect drug response.
• Ethical Issues: Informed consent, access to medication, and off-label drug use.