Pharmacology Exam 1

• Intravenous
• Intramuscular
• Dermal
• Subcutaneous
• Oral
• Sublingual
• Inhalation

• Fast
• Bypasses absorption barriers
• May give a larger volume of drug over a longer period of time

• May not recall drug from circulation after administration
• Drug may precipitate
• Fast administration of the drug may cause an embolism

• High blood supply to muscles
• fast delivery of large quantities of drug
• control of absorption
• cold = slows absorption
• oily vehicle slows absorption
• enhanced absorption by rubbing area to increase blood flow

• Irritation
• Damage from drug

• May be removed easily
• avoid GI tract

• Poor absorption due to layers of skin
• Skin irritation
• Drug must be lipid soluble

• Better blood supply than dermal = better absorption
• enhanced absorption by dissolving subcutaneous connective tissue

• most economic
• convenient
• no skilled health care provider to administer

• irritation to stomach
• subject to 1st pass effect

Metabolism by the liver before circulation to the rest of the body

• Stomach
• Small Intestines

• Small Intestines
• Larger surface area
• more blood supply due to surface area
• bile acids and salts secreted increase absorption of lipid soluble drugs

• high absorption due to blood supply
• no first pass effect

dosage form must be small

good absorption for gas or volatile drugs due to high surgace area and blood supply of alveoli

• Lipid
• Protein
• Aqueous Channels/pores

• Passive Transfer
• Specialized Transfer

• Simple diffusion
• Filtration

• Facilitated Diffusion
• Active Transport

• May give up a proton
• Unionized form may move into the cell

• pH of side 1 and side 2
• Ability of the drug to ionize
• lipid solubility of the unionized form

pH=pKa+log([Base]/[Acid])

• Increase the reactants to increase the products A^-+H⁺ <=> AH
• Increase [H⁺] = decrease the pH
• Manipulate the opposite side
• Reduce [H⁺] on side 1 = increase the pH
• AH on side 1 dissociates to compensate by releasing H⁺
• AH is pulled from side 2 to make up for the loss, resulting in more AH formed on side 2 from A^- and H⁺

Utilize carrier proteins

• Carriers are finite in number and may reach saturation
• Carriers have specificity

Carries drug down its concentration gradient

• Carries drug against its concentration gradient
• Requires energy

food acts as a barrier to drug absorption

• prolonged gastric emptying time
• food and drug stay in the stomach for a longer time
• bile acids and salts are conducive to absorption of lipid soluble drugs

• Contain positive and negative charges which may bind drug
• forms chelate with drug
• drug is not absorbed

good for making tablets into a solution

• decreased GI secretions
• decreased GI motility
• decrease in blood flow to GI tract
• decreased surface area of GI tract
• decreased enterocytes