Drug InteractionsDrug InteractionsTwo or more drugs present in the body at

the same time may interact with each other.

IndependentIndependent The drug does its job without one

affecting the performance of the other.(No interaction)

example: taking amoxicillin to kill the

bacteria causing an ear infection and Tylenol to relieve pain

caused by the ear infection.

This is almost always the aim of the prescribing doctor.

Antagonistic

One drug opposes the action of another drug.

1 + 1 = 1

example: some antibiotics block

the action of the hormone ingredients of birth control pills.

One drug is doubled in its action when taken with another drug.

1 + 1 = 2

example:  aspirin taken along with a blood thinner, such as coumadin, may be the same as taking a double dose of coumadin.

One drug is more than doubled in its action when in the presence of another

drug. 1 + 1 = 3

example: drinking an alcoholic beverage and then taking an antihistamine

may triple the action of the antihistamine and cause

unconsciousness or even death.

Drug Entry Routes Drug Entry Routes

In order for a psychoactive drug

to get to the brain, it must

first enter the bloodstream.

The drug enters into the bloodstream primarily through the wall of the small intestine by being swallowed either in a liquid or solid form

An example would be amoxicillin

tablets, alcohol, Tylenol, etc.

The drug enters the bloodstream by way of a needle being inserted into a vein (IV) muscle (IM), or fat.

Vaccines are usually administered by IM and insulin shots are usually administered through fat.

Morphine and heroin are usually IV.

The drug enters the bloodstream by way of the alveoli in the lungs.

This is the quickest way for a drug

to reach the heart and brain.

Examples are nitrous oxide, ammonia, and ether or other substance not intended for medical use, like paints, markers, aerosols, etc.

The drug enters into the bloodstream through the

skin or mucus membranes. An example would be a

transdermal patch, dip, cocaine, suppositories,etc.