Pharmacology Quiz 2

What is pain?

An unpleasant experience associated with tissue damage, subjective to the patient's perception.

What is the pain threshold?

The point at which a stimulus is perceived as pain.

What does pain sensitivity refer to?

The ability to discriminate between varying degrees of damage.

What is pain tolerance?

The duration of time or intensity of pain that a person will endure before initiating pain responses.

What factors influence pain tolerance?

Psychological factors such as attitude, personality, environment, and culture.

What are analgesics?

Medications that relieve pain without causing loss of consciousness.

What is nociception?

The perception of pain, which varies from person to person.

What are nociceptors?

Receptors that detect damage-associated signals, found in skin, muscle, joints, arteries, and viscera.

What are the two types of nerve fibers involved in pain transmission?

A-delta (Aδ) myelinated fibers and unmyelinated C polymodal fibers.

How does acute stress affect pain modulation?

It triggers the release of endogenous opioids that suppress pain through activation of opioid receptors.

What is the analgesic ceiling effect?

A phenomenon where analgesia does not improve even with higher doses of medication.

What are endogenous opioids?

Naturally occurring peptides in the body that bind to opioid receptors to modulate pain.

Name some types of endogenous opioids.

Enkephalins, endorphins, dynorphins, and endomorphins.

What are endocannabinoids?

Ligands synthesized from fatty acids that bind to cannabinoid receptors to modulate pain.

What substances are released during tissue injury that trigger pain?

Bradykinin, histamine, potassium, prostaglandins, serotonin, and substance P.

What is the role of the dorsal horn in pain perception?

It transfers the pain signal from the peripheral nervous system (PNS) to the central nervous system (CNS).

What are agonists in the context of analgesics?

Synthetic drugs that bind to opiate receptors to relieve pain, such as morphine and oxycodone.

What is the function of antagonists in pain management?

They bind to opioid receptors to prevent responses, useful for reversing opioid overdose.

What are agonist-antagonists?

Drugs that act as agonists at some opioid receptors and antagonists at others.

What are the benefits of using pentazocine and buprenorphine?

They provide pain relief with lower risk of side effects and help manage opioid dependence.

What is the mechanism of action for pentazocine?

It acts as a κ agonist and μ antagonist.

What is the mechanism of action for buprenorphine?

It acts as a μ agonist and κ antagonist.

What are common adverse effects of opioid medications?

CNS depression, respiratory depression, nausea, vomiting, constipation, urinary retention, hypotension, palpitations, flushing, and pinpoint pupils.

What is the role of cyclooxygenase (COX) in inflammation?

COX converts arachidonic acid (AA) into prostaglandins, which increase inflammation, pain, and fever.

How do NSAIDs function?

NSAIDs inhibit COX enzymes, reducing prostaglandin synthesis.

What is the mechanism of action of acetylsalicylate (Aspirin)?

It is an irreversible, noncompetitive inhibitor of COX.

What distinguishes ibuprofen from acetylsalicylate?

Ibuprofen is a reversible, competitive inhibitor of COX.

What is a unique characteristic of acetaminophen (Tylenol)?

It has no anti-inflammatory function and its mechanism of action is not fully understood.

What is the most common source of acetaminophen toxicity?

It is the most common source of self-poisoning, both intentional and unintentional.

What is the antidote for acetaminophen toxicity?

N-acetylcysteine (NAC), which is a glutathione precursor.

What are the signs of acute acetaminophen toxicity?

Nausea, vomiting, anorexia, malaise, fatigue, pallor, diaphoresis, coagulopathies, liver failure, and renal failure.

What defines general anesthesia?

General anesthesia is a complete loss of consciousness and body reflexes, often achieved with multiple drugs.

What is local anesthesia?

Local anesthesia eliminates pain sensation in specific tissues innervated by the anesthetized nerves.

What is procedural sedation?

Procedural sedation is a partial loss of consciousness where the patient can still breathe independently and respond to commands.

What does the Overton-Meyer Rule state about anesthetics?

It states that the potency of anesthetics is related to their lipid solubility; fat-soluble anesthetics are stronger.

What are the components of balanced anesthesia?

Sedatives/hypnotics, analgesics, neuromuscular blockers, and adjuncts.

What is malignant hyperthermia?

A life-threatening pharmacogenomic disorder triggered by certain anesthetics, causing severe muscle rigidity and elevated body temperature.

How is malignant hyperthermia treated?

With cardiorespiratory supportive care and dantrolene, which blocks the ryanodine receptor.

What is the mechanism of action for most anesthetics?

They function through GABA-A potentiation, enhancing the likelihood and duration of channel opening.

What is propofol used for?

It is an IV general anesthetic used for the induction and maintenance of general anesthesia.

What is the role of neuromuscular blocking drugs (NMBD)?

They prevent nerve transmission in skeletal and smooth muscles, facilitating controlled ventilation and intubation.

What is succinylcholine and how does it work?

Succinylcholine is an nAChR agonist that causes rapid onset, short-acting paralysis by preventing repolarization.

What is the action of pancuronium bromide?

It is a competitive antagonist of nAChR, resulting in slower, long-acting non-depolarizing paralysis.

What is the lock-and-key model in relation to proteins?

The active site of a protein has a specific conformation for binding a specific molecule.

What is acetylcholine's role in receptor binding?

Acetylcholine can bind to the active site of several different receptors, functioning like a 'skeleton key.'

What are the two types of cholinergic agonists?

Direct-acting cholinergic agonists and indirect-acting cholinergic agonists (cholinesterase inhibitors).

What is the effect of direct-acting cholinergic agonists?

They bind to cholinergic receptors and include drugs like bethanechol and carbachol.

What distinguishes reversible from irreversible cholinesterase inhibitors?

Reversible inhibitors, like donepezil, competitively inhibit acetylcholinesterase, while irreversible inhibitors form permanent covalent bonds.

What are common adverse effects of cholinergic drugs?

Gastrointestinal issues, bradycardia, hypotension, headache, dizziness, and increased secretions.

What is the primary receptor affected by cholinergic drugs at recommended doses?

Muscarinic receptors.

What are anti-cholinergic drugs and their primary action?

Competitive antagonists that bind to cholinergic receptors, blocking their action.

What are the symptoms of anti-cholinergic drug toxicity?

Confusion, hyperthermia, dry mouth, flushing, and pupil dilation.

What are catecholamines and name three examples?

Catecholamines are hormones released by the adrenal glands; examples include epinephrine, norepinephrine, and dopamine.

What types of receptors do adrenergic drugs target?

α1, α2, β1, β2, and D1-D5 receptors.

What are the general physiological effects of α-adrenergic receptors?

Vasoconstriction and central nervous system stimulation.

What are the effects of β-adrenergic receptors?

Bronchial and gastrointestinal smooth muscle relaxation, glycogenolysis, and cardiac stimulation.

What is the effect of β1-adrenergic blocking drugs on the heart?

They decrease heart rate, prolong SA and AV node intervals, and reduce myocardial contractility.

What is the effect of non-selective β-blockers?

They cause the same heart effects as cardioselective β-blockers but can constrict bronchioles and produce vasoconstriction.

What are the adverse effects of α-adrenergic blocking drugs?

Palpitations, orthostatic hypotension, dizziness, nausea, and dry mouth.

What is the mechanism of action of indirect-acting cholinergic agonists?

They inhibit acetylcholinesterase, resulting in more acetylcholine available at the receptors.

What is pseudo-irreversible inhibition in cholinergic drugs?

It forms a covalent bond that is breakable, resulting in a longer therapeutic effect than reversible inhibitors.

What are the effects of cholinergic stimulation on the gastrointestinal system?

Increased gastric secretions and gastrointestinal motility.

What is the role of dopamine receptors in the body?

They cause dilation of certain blood vessels, including renal, mesenteric, coronary, and cerebral.