Pharmacology Overview Quiz

Pharmacology

• The science of drugs
• Includes classification, pharmacokinetics, pharmacodynamics, side effects, and therapeutic uses

Drug

• A substance used for prevention, diagnosis, treatment, and cure of disease in animals and humans

Pharmacokinetics

• Describes what the body does to the drug
• It is the study of Absorption, Distribution, Metabolism (biotransformation) and Excretion of drugs.

Pharmacodynamics

• The study of the pharmacological and physiological effects of drugs and the mechanism of action of drugs.

Pharmacogenomics

• The study of genetic variations that cause individual differences in drug response.

Branches of Pharmacology

• Medical pharmacology: The study of the beneficial therapeutic effects of chemicals on the body, as well as their toxic effects on parasites infecting the patient.
• Toxicology: The study of the undesirable effects of chemicals on living systems.

Pharmacokinetics of Drugs

• Studies of drugs regarding ADME (Absorption, Distribution, Metabolism, Excretion)
• The science dealing with the movement of a drug over time through the body.

Onset of Action (Onset Time)

• The duration of time it takes for a drug's effects to become prominent after administration.

The Peak Time (tmax)

• The time at which the body displays the maximum plasma concentration of a drug.

Routes of Drug Administration

• Enteral (through the gastrointestinal tract)
• Parenteral (injections)

Enteral Routes

• Oral
• Sublingual
• Rectal

Parenteral Routes

• IV (Intravenous)
• SC (Subcutaneous)
• IM (Intramuscular)

Factors Determining Route of Administration

• Properties of the drug (water or lipid solubility, ionization, etc.)
• Therapeutic objectives (rapid onset, long-term administration, localized effect)

Enteral Administration

• Oral: Swallowing the drug (absorption occurs in the stomach and duodenum)
• Sublingual: Placement under the tongue for direct absorption into the bloodstream, bypassing the gastrointestinal tract.

Advantages of Sublingual Administration

• Rapid absorption
• Rapid onset of action
• Easy removal of excess drug from the mouth
• Bypasses the first-pass effect

Oral Dosage Forms (oral formulations)

• Tablets:
• Coated tablets: sugar-coated for taste masking
• Enteric coated tablets: dissolve only in the intestine
• Capsules:
• Hard gelatin capsules: contain powder
• Soft gelatin capsules: contain liquid
• Syrup (e.g., cough syrups)
• Suspension (mixture of solid in liquids e.g., antibiotics).

Rectal Administration

• Used when the oral route is unavailable.
• Useful if a drug induces vomiting, if the patient is vomiting, or if the patient is unconscious.
• Bypasses the first-pass effect to some extent (50%).
• Suitable for children.