Introduction to Drugs 1 University of Hawaii Hilo Pre -Nursing - - PowerPoint PPT Presentation

Introduction to Drugs

University of Hawai‘i Hilo Pre-Nursing Program NURS 203 – General Pharmacology Danita Narciso Pharm D

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Learning objectives

 Understand and differentiate between a broad definition of a drug and a medical definition  Understand the advantages of drugs created from natural sources and drugs synthesized in the lab  Know the characteristics of the clinical trial phases  Know the characteristics of the perfect drug  Know the advantages and disadvantages of each dosage form discussed

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What is a drug?

 Is this a drug?

 Tylenol

Substances that act

• n biological systems

at the chemical level and alter their function.

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What is a drug?

 Is this a drug?

 Tylenol

 Yes

Substances that act

• n biological systems

at the chemical level and alter their function.

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What is a drug?

 Is this a drug?

 Tylenol

 Yes

 Alcohol

Substances that act

• n biological systems

at the chemical level and alter their function.

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What is a drug?

 Is this a drug?

 Tylenol

 Yes

 Alcohol

 Yes

Substances that act

• n biological systems

at the chemical level and alter their function.

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What is a drug?

 Is this a drug?

 Tylenol

 Yes

 Alcohol

 Yes

 Grapefruit juice

Substances that act

• n biological systems

at the chemical level and alter their function.

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What is a drug?

 Is this a drug?

 Tylenol

 Yes

 Alcohol

 Yes

 Grapefruit juice

 Yes

Substances that act

• n biological systems

at the chemical level and alter their function.

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What is a drug?

 Medical definition

 Substances used in the diagnosis, treatment, or prevention of disease in humans

• r animals.

 Tylenol?  Alcohol?  Grapefruit juice?

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What is a drug?

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What is a drug?

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What is a drug?

Drug Dosage Form

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Where do drugs come from?

 Natural sources

 Plants

 ____________

 Animals

 ____________

 Minerals

 ____________

 Synthetic sources

 Plants (power), nah…. The lab

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A new drug is born!

 No longer guessing  Investigational New Drug (IND) application  Clinical trials

 Phase I

 ___________

 Phase II

 ___________

 Phase III

 ___________

 Phase IV

 ____________

 Expedited approval

 _____________

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The perfect drug

 Would exert a desirable action  Have no side effects – or very few  Reach its destination at the right concentration at the right time  Not overstay its welcome – remain at its site of action for only for the necessary period of time  Leave when the job is done – rapidly and completely

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How do drugs attempt to reach perfection?

 Delivery or dosage forms

 Oral  Intravenous  Intramuscular  Subcutaneous  Buccal and sublingual  Inhalation  Topical  Rectal  Transdermal

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Oral

 Swallowed

 Tablet, capsule, syrups, and suspensions  Must get absorbed into the blood stream and delivered to the site of action

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Intravenous

 Straight into the vasculature

 Injectable – arteries and veins  Absorption not necessary

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Intramuscular

 Into the muscle

 Many vaccinations  Not 100% bioavailable, faster absorption than oral

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Subcutaneous

 Fatty layer of the skin

 Insulin and lovenox  Slower absorption than intramuscular but anticoagulants ok

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Buccal and sublingual

 Absorbed through mucosal tissue and under the tongue

 Nicotine gum and Zofran ODT  Avoids metabolism, can be absorbed fast or slow

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Inhalation

 Into the lung tissue

 Inhaler devices and nebulizers  Closest to target tissues, coordination issues

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Topical

 Not just for the skin– eye, ear, nose, throat, airway, vagina

 Lozenges, drops, sprays, creams, and ointments  Local effects, absorption varies

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Rectal

 Suppository

 Antiemetics, antipyretics, & antiepileptics  Some first pass effect, helpful for those who cannot swallow

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Transdermal

 To the skin

 Fentanyl patch, nicotine patch, & Vivelle dot  For SYSTEMIC effects

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Questions

Please email me if you have any questions!

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