(P2) Lab 8 Q&A Set 2 Flashcards
A 37-year-old man complained to his physician of persistent, intolerable pain in his left leg that started about 2 days earlier. He reported that he had tried several over-the-counter pain medications without success. One month earlier, the patient underwent the amputation of his left leg following an accident at work. Physical examination revealed that pain could be elicited by a no noxious stimulus applied to the region of amputation. The physician made a preliminary diagnosis and prescribed a drug for pain. Which of the following drugs would be appropriate for this patient?

Venlafaxine

Venlafaxine
Define
Antidepressant Medication of Serotinin-norepinephrine reuptake inhibitor class. (SNRI’s)
USE: to tx major depressive disorder, generalized anxiety disorder, panic disorder and Social Phobia
ALSO may be used for CHRONIC PAIN
Phenobarbital
define class:
BARBITURATES
Give four examples of barbiturates
and
their duration of action
- Phenobarbital* (Luminal)—long- acting/1–2 days.
- Pentobarbital* (Nembutal)—short- acting/2–8 hours.
- Amobarbital* (Amytal)—short-acting
- Thiopental* (Pentothal)—ultra–short-acting/10–20 minutes.
Phenobarbital
(Barbiturates)
MOA:
Like benzodiazepines, barbiturates increase the duration of GABA action on Cl– entry into the cell, which results in membrane hyperpolarization and a decrease in neuron excitability.
Barbiturates do not bind to benzodiazepine receptors.
phenobarbital
(Barbiturates)
What are the therapeutic indications
for
barbiturate administration?
Induction of anesthesia—thiopental Anticonvulsants—phenobarbital Anxiety—rarely
- Decrease the activity of Brain and NS
- Prevent and Treat Seizures
- also short term sedation
- anxiolytic- CNS depressant
BARBITURATES
Phenobarbital
ROA:
IV, PO, or IM
Phenobarbital
What are the pharmacokinetic properties of barbiturates?
They are metabolized in the liver and excreted in the urine.
Does barbiturate dependency occur?
Yes.
Abrupt cessation can lead to severe withdrawal symptoms (tremor, restlessness, nausea, seizures, and cardiac arrest).
For whom are
barbiturates contraindicated?
For patients who have acute intermittent porphyria, because they increase porphyrin synthesis
phenobarbital (Barbiturates)
What are the adverse effects of these drugs?
-Drowsiness and decreased motor control Induction of the P-450 system, which can
therefore decrease the effect of other
drugs metabolized by these enzymes
- Addiction
- In high doses, respiratory depression and coma
- Allergic reactions, especially in patients with asthma
What is acetaminophen
and
Clinical indications
also known as Tylenol
Acetaminophen is an over-the-counter antipyretic and analgesic medication that is routinely administered.
-Fever and mild-to-moderate pain
How does acetaminophen work
This drug acts by inhibiting cyclooxygenase and thus prostaglandin synthesis in the CNS.
It has much less of an effect on cyclooxygenase in peripheral tissues, which accounts for its weak anti- inflammatory effects.
What are antipsychotic drugs
Antipsychotics, also known as neuroleptics, are drugs used primarily to treat psychotic states such as schizophrenia, delusional disorder, and other hallucinatory states
Antipsychotics
MOA:
Antipsychotics block various receptors including cholinergic, adrenergic, serotoninergic, muscarinic, and histamine receptors.
However, their antipsychotic actions are primarily thought to be due to blocking of dopamine receptors in the central nervous system, particularly the D2 receptors in the mesocortical and mesolimbal systems of the brain.
Do antipsychotic agents differ in potency?
Yes—a drug’s potency parallels its affinity for D2 receptors.
Haloperidol and thiothixene
are high-potency drugs because they have high affinity for the D2
receptors, whereas chlorpromazine and thioridazine are low-potency drugs because they have low affinity for D2 receptors.
How are antipsychotics usually administered?
these drugs are given orally;
or
intramuscularly if the patient is noncompliant.
Describe the absorption and metabolism of the traditional antipsychotics.
They are variably absorbed orally but they pass into the brain easily and have a large volume of distribution. Metabolism occurs by the cytochrome P-450 system in the liver.
Antipsychotics
What is the onset of action?
Antipsychotics may not become effective for several weeks to months.
-sedation and other side effects can occur rapidly.
Can these drugs cure illnesses such as schizophrenia?
No!
Antipsychotics only reduce the symptoms of the illness; they cannot cure the illness.
Name 6 examples of
atypical antipsychotic drugs
- Clozapine (Clozaril)
- Risperidone (Risperdal)
- Olanzapine (Zyprexa)
- Aripiprazole (Abilify)
- Quetiapine (Seroquel)
- Ziprasidone (Geodon)
Why are these drugs considered “atypical”?
They are newer drugs and in addition to blocking dopamine receptors, atypical antipsychotics also produce significant therapeutic effects through the blockade of serotonin (5-HT2) receptors.
They are also rarely associated with extrapyramidal side effects.
Describe the actions of
clozapine
This agent is a dibenzodiazepine derivative.
It differs from traditional antipsychotics in its potent blockade of serotonin (5-HT2) receptors*, along *with
the usual dopamine blockade.
Clozapine
What is it used for?
Clozapine has been effective in treating cases of schizophrenia that are refractory to other neuroleptic drugs.
It is especially effective in treating the negative symptoms of schizophrenia (blunted emotion, withdrawal, reduced ability to form relationships)




























