Chapter 10Analgesic and

Antipyretic Agents

Analgesics

Analgesic drugs relieve pain

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Pain Definition

Pain is what the patient says it is!

0-10 scaleWong-Baker FACES scaleInfant behavioral scales

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Pain

Pain = brain’s perception/interpretation of nerve signals ◦Treat all complaints of pain◦Pain: the fifth vital sign

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Pain Transmission: Gate Theory

Most common and well-described theory of pain

Uses the analogy of a gate to describe how impulses from injured tissues are sensed in the brain

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Neurotransmitters

Endogenous neurotransmitters◦Endorphins◦Enkephalins

Produced to fight pain◦Marathon runners and cyclists

Bind to opioid receptorsInhibit transmission of pain by

closing the gate

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Management of Pain

Treat the cause. Select a safe analgesic. Select the analgesic that

provides effective relief. Provide psychological support.

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Management of Pain

Non-pharmacologic nursing actions: ◦position change, massage, heat, reassurance, guided imagery, laughter, distraction, music/art therapy etc.

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Opioid Analgesics

Opium has been used for thousands of years to alleviate pain.

Opium is derived from the poppy plant.

Opium produces pain relief by attaching to pain receptors

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Narcotics (Opioid Analgesics)

Narcotics are derivatives of opium

strong pain relievers◦Induce alteration in mental status

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Effects of Opioid Analgesics

Respiratory depressionEuphoriaNausea and vomitingUrinary retentionDiaphoresis and flushingPupil constriction (miosis)Constipation

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Uses for Opioid Analgesics

Main: ◦to alleviate moderate to severe pain

Also:◦Cough suppression◦Diarrhea treatment

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Complications of Opioid Analgesics

Respiratory: rate slows and depth becomes shallow◦12-20 breaths/minute normal◦May slow to less than 8/minute

Constipation concerns

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Opioids: Nursing Assessments

Thorough historyBaseline v/s, assessmentspotential contraindications, drug

interactions?If respirations are below normal, hold med

and consider NarcanAssess pain after Narcan administration –

alternate medication?

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Opioid Analgesics: Nursing Implications

Oral forms–take with food Ensure safety measures

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Opiates: Opioid Tolerance

A common response to chronic opioid treatment

Larger doses of opioids required

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Opiates: Physical Dependence

Physiologic adaptation to the presence of an opioid

If in need of pain relief, give the medication

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Opiates: Psychological Dependence (Addiction)

A pattern of compulsive drug use when the medication is not needed for physical pain relief

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Opioid Analgesics: Nursing Implications

Law: narcotics must be kept under a double lock

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Opioid Analgesics: Therapeutic Effects

Monitor for therapeutic effects◦Increased comfort◦Activities of daily living improved

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Opiate AntagonistsNaloxone (Narcan) and naltrexone

(ReVia)◦Opiate antagonists◦Bind to opiate receptors, prevent response

◦reverses opioid-induced respiratory depression

Overdose treatment◦Narcan◦Charcoal

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Opioid Analgesics: Nursing Implications

Rotate site for IM injections.Follow guidelines for IV administration (dilution, rate of administration, etc)

Check dosages carefully

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Opioid Analgesics: Nursing Implications

Prevent constipation.◦Provide fluid and fiber.

Prevent respiratory depression.Provide instruction for clients.

◦Drug administration◦Position changes

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Analgesic Agents

Analgesic agents◦Salicylates (ASA)◦Acetaminophen (Tylenol)◦Combination narcotic and non-narcotic analgesics

Anti-inflammatory analgesic agents◦Nonsteroidal anti-inflammatory drugs (NSAIDs)

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ASA (Acetylsalicylic Acid)

Used for more than 100 yearsCurrently is primarily used for its effects on platelets

Treats mild to moderate painAntipyretic effect

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ASA: Side Effects

Gastrointestinal irritation and bleedingIncreases bleeding timeTinnitusChildren: Reye’s syndrome

◦Risk increases if recent viral infection◦Causes encephalopathy and liver dysfunction

◦Symptoms include intractable vomiting, and altered mental status

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ASA Overdose treatment

CharcoalCorrection of acid-base balanceDialysis

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Analgesic Agents: Acetaminophen

◦mild to moderate pain◦antipyretic◦Weak anti-inflammatory◦Minimal effect on CNS◦FDA in 2011 lowered maximum daily dose recommendation to 3 grams for healthy adults

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headache pain

Most common: tension and vascular headachesASA (aspirin), APAP (acetaminophen),

ValiumMigraine most common form of vascular

headache◦beta-blockers, calcium channel blockers, ergot and ergot-like drugs: Ergostat, ergotamine tartrate, dihydroergotamine mesylate (D.H.E.)

◦Eletriptan hydrobromide (selective serotonin receptor agonist)

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Headache pain

Migraine: ◦Imitrex (sumatriptan): use at headache onset – not preventive

PO and intranasal forms may be repeated Q 2 hours until max daily dose reached or headache minimized

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Acetaminophen: Side Effects

Acute overdose causes hepatic necrosis.◦Doses of 150 mg/kgLong-term ingestion of large doses can result in nephropathy

Maximum healthy adult dosage is now 3 grams/day

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Acetaminophen: Acute Overdose

Treatment: acetylcysteine (mucomyst)◦Oral form◦IV form now approved

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