Pain and Analgesic Drugs Flashcards by claire b🩻

What is Nociception?

Detection of noxious stimuli or stimuli that are capable of damaging tissue

How well did you know this?

Not at all

Perfectly

What is pain?

Unpleasant sensory and emotional experience associated with actual or potential tissue damage or described in terms of such damage

How well did you know this?

Not at all

Perfectly

What are the four processes of pain?

Transduction
Transmission
Perception
Modulation

How well did you know this?

Not at all

Perfectly

What is acute pain?

Sudden onset
Usually subsides once treated

How well did you know this?

Not at all

Perfectly

What is an example of a nociceptive stiumulus?

Stepping on a nail
Causes acute pain via activation of nociceptive pathways

How well did you know this?

Not at all

Perfectly

What is chronic pain?

Persistent or recurring pain
-More than 6 weeks
Difficult to treat

How well did you know this?

Not at all

Perfectly

Examples of chronic pain?

Mild, musculoskeletal pain
Deep pain
Neuropathic pain
Chronic pain of indeterminate cause

How well did you know this?

Not at all

Perfectly

What is neuropathic pain?

Pain induced by injury or disease of the somatosensory system

How well did you know this?

Not at all

Perfectly

What causes neuropathic pain?

nerve injury
Infections of the NS
e.g, phantom limb pain, trigeminal neuralgia, shingles (postherpetic neuralgia), diabetic neuropathy

How well did you know this?

Not at all

Perfectly

How does neuropathic pain develop?

Slowly
outlasts healing of original injury

How well did you know this?

Not at all

Perfectly

Examples of neuropathic pain?

Allodynia
Hyperalgesia
Causalgia (burning)

How well did you know this?

Not at all

Perfectly

What are some sources of pain?

Somatic (superficial)
Visceral (vascular, respiratory)
Referred
Cancer (breakthrough)
Phantom
Neuropathic
Psychogenic
Central

How well did you know this?

Not at all

Perfectly

What are the two groups of pain medications?

Analgesic
Anesthetic

How well did you know this?

Not at all

Perfectly

What do analgesic pain medications do?

Selectively blocks the sensation of pain without
blocking other symptoms or loss of consciousness

How well did you know this?

Not at all

Perfectly

What do local anesthetic pain medications do?

Blocks nerve conduction and all local sensations (including pain)

How well did you know this?

Not at all

Perfectly

What do general anesthetic pain medications do?

Cause loss of sensations and unconsciousness

How well did you know this?

Not at all

Perfectly

Where is the site of action of opioids?

Higher centres
Spinal cord

How well did you know this?

Not at all

Perfectly

What do opioids alter in higher centres in the brain?

Psychological response to pain
-Pain can still be felt but produces less suffering
-Changes perception

How well did you know this?

Not at all

Perfectly

What do opioids do in the spinal cord?

Reduce neurotransmitter release from terminals pain fibres in dorsal horn of spinal cord
-Modulation

How well did you know this?

Not at all

Perfectly

How do opioids work?

The drugs bind to opioid receptors

How well did you know this?

Not at all

Perfectly

What is an opiate?

Any drug derived from opium
e.g, Morphine, codeine

How well did you know this?

Not at all

Perfectly

What is opium?

“juice” of the poppy (Papaver somniferum)

How well did you know this?

Not at all

Perfectly

Why do different opioids have different properties?

They have various affinity and activation for different opioid receptor subtypes
and pharmacokinetic differences

How well did you know this?

Not at all

Perfectly

All opioid analgesics are what?

Full agonists of partial agonists at µ and/or κ receptors

How well did you know this?

Not at all

Perfectly

What are the kinds of opioid receptors?

µ (mu) receptors κ (kappa) receptors δ (delta) receptors

µ (mu) receptors

Analgesia Brain and spinal cord

Which parts of the brain have µ (mu) receptors?

Cortex, medulla, thalamus, limbic system, amygdala

κ (kappa) receptors

Analgesia Brain and spinal cord -Dysphoria and hallucinations

What are the pharmacological properties of opioids?

Analgesia Sedation and mental clouding Euphoria and tranquility Antitussive -no cough reflex Depression of respiratory centre Nausea, vomiting Miosis (pin point pupil) Tolerance, serious dependence Constipation Postural hypotension Dilation of cutaneous blood vessels, warm skin Urinary urgency but difficult urination Biliary colic and epigastric distress

Which pharmacological properties of opioids are associated with µ (mu) receptors?

Analgesia (and kappa) Euphoria and tranquility (and delta) Depression of respiratory centre Miosis (pin point pupil) (and kappa) Tolerance, serious dependence Constipation (and delta)

Examples of opioid analgesics?

Morphine Methadone (longer action than morphine) Fentanyl Diamorphine (Heroin) Levorphanol Hydromorphone Oxycodone Codeine

What are opioids used for?

Alleviate mild, moderate to severe pain (depends on opioid or given with adjuvant agent to relieve pain) Cough centre suppression Treatment of diarrhea Balanced anaesthesia

What opioid suppresses cough centre?

Codiene

What opioid is used for the treatment of diarrhea?

Loperamide

What opioid is used to balance anasthesia?

Fentanyl

What is morphine used for?

Acute and chronic pain

What drug are other analgesics often compared to?

Morphine it is the standard Equianalgesic doses

Which receptors does morphine mostly bind to?

mu-opioid receptors in the brain and spinal cord

How is morphine administered?

IV, IM, SC, PO, intrathecal

What is half-life (T 1/2) of morphine?

2-4 hours

Where is morphine metabolized?

Extensive liver metabolism -First-pass metabolism -Inactivation -Liver disease

What happens if morphine is used during pregnancy?

Dependance, crosses placenta

What happens if morphine is used while breastfeeding?

Enters breast milk

What is breakthrough pain?

Transient episodes of pain, while chronic pain is controlled Requires access to rescue medication

How is cancer pain treated?

Sustained release morphine (MS Contin) Around The Clock (ATC) NSAIDs Adjuvants Other analgesics when needed

How is MS Contin administered?

What is MS Contin?

MS = morphine sulfate Contin = continuous/sustained release

What is the most common non-narcotic analgesic?

NSAIDs

What are some examples of adjuvants?

Antidepressants eg amitriptyline (Elavil) Antiseizure drugs eg carbamazepine Glucocorticoids

When is morphine use contraindicated or should be used very cautiously?

Severe asthma or other respiratory insufficiency - causes RESPIRATORY depression Hepatic dysfunction Elevated intracranial pressure (ICP) -- exacerbates it Pregnancy

What is the #1 serious adverse effect associated with opioids?

Respiratory depression

What other adverse effects are associated with opioid analgesics?

CNS depression (could lead to coma) Nausea and vomiting Constipation Hypotension Histamine release Urinary retention Diaphoresis and flushing Pupil constriction (miosis)

When is nausea and vomiting caused by opioids greatest?

On 1st dose then decreases

Why do opioids cause hypotension?

Cause dilation of peripheral arteries and veins (histamine release)

What happens because of histamine release associated with opioid use?

Itchiness Rash Dilation of peripheral arteries and veins

What other drugs do opioids have cumulative effects with?

CNS depressents e.g, antipsychotics, antihistamines, sedatives (benzodiazepines, barbiturates) Ethanol (alcohol)

What are some moderate opioids?

Codeine (3-methylmorphine) Oxycodone Buprenorphine Codiene

What are properties of codiene?

Less analgesia and respiratory depression Antitussive Liver metabolism (~10% of oral dose) = unpredictable Often combined

What is Codiene often combined with?

Acetaminophen in Tylenol 1, 2 and # Acetylsalicylic acid in 222's or 292

What is required for the activation of Oxycodone?

Metabolism

What is there potential for with oxycodone use?

Abuse (addiction)

What is oxycodone also kown as?

Oxycontin or Percodan

What is oxycodone widely used in combination with?

Acetaminophen ( aka percocet)

What are some opioid antagonists?

Naloxone (Narcan) Naltrexone

What are opioid antagonists used for?

Complete or partial reversal of opioid induced respiratory depression

What is the half-life of Naloxone?

~2 hours -Shoter half-life than morphine and other ropioids

How is Naloxone administered?

IV, IM, SC and nasal

What way is naloxone administered in rescue kits?

IV or nasal

How is opioid addiction treated?

Methadone program Buprenorphine + nalosone (suboxone)

What is Buprenorphine + naloxone (suboxone)?

SL tablet Alternative to methadone -help you use other opioids less

What is a common physiological result of chronic opioid treatment?

Tolerance

What is opioid physical dependance?

State that develops in which an abstinence syndrome will occur if a drug is abruptly withdrawn Drug must be administered to maintain normal function Occurs with other unrelated drugs classes On abrupt discontinuation or when an opioid antagonist is administered

What is narcotic withdrawal?

Opioid abstinence syndrome Unpleasant but not dangerous

What are withdrawal symptoms?

Anxiety Irritability Chills and hot flashes Joint pain Lacrimation Sneezing Rhinorrhea Diaphoresis Nausea Vomiting Abdominal cramps Diarrhea

Physical dependence is NOT the same as what?

Addiction

What is addiction?

Substance dependence syndrome

What are both parts of the body's response to the presence of opioid drugs?

Tolerance Physical dependence

Oral opioids should be taken with what

Food -minimize gastric upset

When should opioid dose be withheld, and physician should be contacted?

If there is a decline in the client's condition or is VS are abnormal -Especially if respiratory rate is less than 12

How can respiratory depression caused by opioids manifest?

Less than 12 breaths per minute Dyspnea Diminished breath sounds Shallow breathing

How can constipation caused by opioids be managed?

Take with adequate fluid and fibre intake stool softener (docusate) and or stimulant (senna) daily

How can ortjostatic hypotension caused by opioids be managed?

Instruct to change positions slowly

Pain and Analgesic Drugs Flashcards

(82 cards)