Adrenergic Agents: ALPHA-AND BETAADRENERGIC AGONISTS Flashcards
are also called sympathomimetic drugs
because they produce effects similar to those produced by the
sympathetic nervous system.
ADRENERGIC DRUGS
ADRENERGIC DRUGS Groups: (chemicals)
Catecholamines
Noncatecholamines
Actions
direct-acting, in which the drug acts directly on the organ or tissue
innervated (supplied with nerves or nerve impulses) by the sympathetic
nervous system
indirect-acting, in which the drug triggers the release of a
neurotransmitter, usually norepinephrine
dual-acting, in which the drug has direct and indirect actions.
, in which the drug acts directly on the organ or tissue
innervated (supplied with nerves or nerve impulses) by the sympathetic
nervous system
direct-acting
in which the drug triggers the release of a
neurotransmitter, usually norepinephrine
indirect-acting
in which the drug has direct and indirect actions.
dual-acting
CATHECHOLAMINES FAMILY NAME
-Ine , -Nol
ALPHA-ANDBETA-ADRENERGICAGONISTS
INDICATION
These drugs generally are
indicated for the treatment of
hypotensive states or shock,
bronchospasm, and some
types of asthma
PHARMACOKINETICS of ALPHA-ANDBETA-ADRENERGICAGONISTS
❏ These drugs are generally absorbed
rapidly after injection or passage
through mucous membranes.
❏ They are metabolized in the liver and
excreted in the urine.
❏ When used in emergency situations,
they are given intravenously (IV)to
achieve rapid onset of action
PHARMACODYNAMICS OF ALPHA-ANDBETA-ADRENERGICAGONISTS
- When catecholamines combine with alpha-adrenergic receptors or beta-adrenergic
receptors, they cause either an excitatory or
inhibitory effect. - Typically, activation of alpha-adrenergic
receptors generates an excitatory response
except for intestinal relaxation. Activation of
the beta-adrenergic receptors mostly
produces an inhibitory response, except in
the cells of the heart, where norepinephrine
produces excitatory effects. - Catecholamines also produce a positive
chronotropic effect, which means they cause
the heart to beat faster. - As catecholamines cause blood vessels to
constrict and blood pressure to rise, heart
rate can fall as the body tries to compensate
and prevent an excessive rise in blood
pressure. - Catecholamines can cause the Purkinje fibers
to fire spontaneously, possibly producing
abnormal heart rhythms, such as premature
ventricular contractions and fibrillation. - Epinephrine is more likely than
norepinephrine to produce this spontaneous
firing.
These drugs are generally absorbed
rapidly after injection or passage
through mucous membranes.
ALPHA-ANDBETA-ADRENERGICAGONISTS
In emergency situations how is ALPHA-ANDBETA-ADRENERGICAGONISTS given and why
given intravenously (IV)to
achieve rapid onset of action
What effects does Catecholamines give when combined with alpha-adrenergic receptors or beta-adrenergic receptors
excitatory or
inhibitory effect.
Typically, activation of alpha-adrenergic
receptors generates an _______ except for __________
excitatory response
except for intestinal relaxation
Activation of the beta-adrenergic receptors mostly produces an _______ except in __________
inhibitory response, except in
the cells of the heart, where norepinephrine
produces excitatory effects.
