Pharmacology

The study of drugs and their actions on the body

The study of drugs used to cure, treat, or prevent disease

A combination term for pharmacology and therapeutics

Collective of all aspects of disease and not just the pharmacotherapy

• Drugs are classed or grouped according to the drug use
• For example, therapeautic classification of bronchodilators can have several drug classes (xanthines, beta adrenergics, parasympatholytics)

Drugs with similar characteristics

• drugs are derived from a variety of sources:
• Plants
• animals
• minerals
• chemicals
• Recombinant DNA 

Chemically synthesized, but in the future may be bioengineered

• Describes the chemical structure and is long and very complicated
• This has little clinical use but is needed to make the drug

• Given by United States Adopted Names (USAN) council
• Not owned by a particular company, called the nonproprietary name, and usually writted in lowercase
• Example: albuterol sulfate

• Owned by company that discovered and produced the drug
• Example: Sudafed^registered is the trade name for generic psudoephedrine
• Trade names are usually capitalized and have the regestered trademark symbol

Measures the amount of drug absorbed into circulation

• Drug solubility
• Dosage form
• Route of administration
• pH

• Oral
• Sublingual
• Rectal
• Nasogastric tube
• Intravenous
• Intramuscular
• Transdermal
• Inhalation

Kinesis means movement, and this literally means what happens to a drugfrom the time it enters the body to the time it leaves the body

• Absorption
• Distrubtion
• Metabolism
• Elimination

• This is the rate limiting step
• In other words, how fast it takes the drug to dissolve determines the rate of effect
• IV is the fastest because it bypasses the absorption process by going directly into the bloodstream

Major vehicle for distrubtion is the bloodstream

• Blood fat
• Fat
• Water solubility
• Protein binding

After the drug has been absorbed and distributed, the body works to break it down via metabolism into several components called metabolites

The liver

This is the last step of pharmacokinetics, where the drug is excreted from the body

• Urine
• Feces
• Pulmonary system
• Skin
• Hair

• Time it takes for the concentration of the drug to decrease by one-half after adminstration
• Drugs with short half lives don't stay in the bosy long

• After being absorbed, some drugs do not go directly into circulation but pass threw the liver first, where enzymes can begin to inactivate.
• This is one reason why equivalent oral doses are higher than IV doses

• A continuous infusion gives a regulated, consistent dosage over time of drug concentration in the plasma
• Maximum concentration in the body

• A size of the drug molecule
• Ionization of drug
• Lipid solubility across the lipid cell membrane

More potent than drugs with a low ED 50

The ration between the minimun effective dose and the maximun tolerated dose

The stregth of binding between a drug and a receptor

• Binds with receptor (affinity) and causes a response
• In other words, it activates the receptor

Binds with receptor (affinity) but has little or no response

• The sum of the effect of two drugs given together is equal to each of them given separately but at the same time
• 1 + 1= 2

• Giving two drugs together results in a greater effect than expected if given seperately
• 1 + 1= 3

• One of the drugs has no direct effect yet increases the effect of the other drug
• 1 + 0= 3

• Central nervous system
• Perpheral nervous system

Comprised of the brain and spinal cord

• Comprised of all the nerves outside the brain and spinal cord
• Afferent and Efferent nerves

Carry sensory information from parts of the body to the brain for processing

• Carry impulses away from the brain and spinal cords
• Also known as motor nerves

• Somatic nervous system
• Autonomic nervous system

Controls skeletal muscle movement during voluntary movement and is under concious control

• The involuntary or automatic respons
• Regulates the cardiopulmonary and digestive systems

• Sympathetic
• Parasympathetic

• Alert system for stressful situations
• Fight or fight response

• Concerned with daily body maintenance and maintaining a homeostatic enviroment
• Sleep and Eat system

Supension of solid or liquid particles within a gas

Delievery of either solid or liquids into the respiratory tract for therapeutic purposes

• To humidify inspired gas, which may be dry or humidity deficient
• To improve the mobilization and elimination of secretions
• To deliever medications to the respiratory tract

• Smaller requried doses
• Quick drug response
• Fewer less sever side effects
• Painless and convenient

• Difficult to delivery percise dose
• Requries patient compliance and education
• Equipment maintenance

These particles get stuck in the upper airways (nose and mouth)

These particles penetrate to larger bronchi

These particles pentrate to lower airways, where most bronchodilators are needed

• These particles penetrate to the alveoli
• May also be breathed right back out

• Are quite efficient
• They have a very low dead volume and may not need diluent, which shortens treatment time
• However they are very expensive

• Desensitize the allergic response
• Which then prevents or decreases the incidence of asthma

• The portion of the dose that cannot be nebulized
• Can be as little as 1 to 3 ml

60 to 70% of patients do not use the MDI correctly

• Devices that deliver the drug in powder form to the lungs for absorption
• Have no propellant or external power source
• Small self generating devices
• Patient must generate greater than 50 liters per minute for the device to properly aerosolize the dry powder
• Difficult for small children and someone in acute respiratory distress to use
• Works well in cold weather unlike MDI

• Found at the skeletal muscles in the somatic system and at all preganglionic sites in the parasympathetic and sympathetic nervous system
• These receptors simply pass the signal on to the postsynaptic neuron

• Found at the postganglionic site of the parasympathetic nervous system
• ACh binds found on involuntary muscles or glands

Acetychlinestrase (AChE)

• Cholinergics
• Parasympathomimetics

Causes slowing of the heart and bronchonstruction

Beta1 speed up the heart rate and beta2 causes bronchoconstruction

• Smooth muscle of the blood vessels
• Vasoconstriction

• Found primarily in cardiac muscle
• increase in heart rate
• increase in conduction
• increase in contraction

• Smooth muscle of airways and certain muscles
• Vasodilation
• bronchodilation

• All autonomic preganglionic and at parasympathetic postganglionic synapses
• Somatic system or preganglionic sites

• Drugs that stimulate parasympathetic receptor
• Responses cause slow heart rate and bronchoconstruction