PAIN MEDICATIONS
dr. Ave Olivia Rahman, MSc.
Bagian Farmakologi FKIK UNJA
Pain
According to Duration
Acute Pain
Chronic Pain
According to Type
Nociceptive Pain
Inflammatory Pain
Neuropathic Pain
Pain Medications
Non opioid analgesics
Antipyretics
Nonsteroidal anti-inflammatory
drugs (NSAIDs)
Opioid analgesics
Anesthetic drugs.
Nonopioid Analgesics,
Antipyretics, and NSAIDs
The drug classes included in this group
are:
Salicylates (especially aspirin), widely
used
Para -aminophenol derivative
(acetaminophen)
NSAIDS
Phenazopyridine (urinary tract
analgesic).
Salicylates
common salicylates include:
Aspirin
Choline magnesium trisalicylate
Choline salicylate
Diflunisal
Salsalate
Sodium salicylate.
Pharmacokinetics
The pure and buffered forms of aspirin
are absorbed readily, sustained -release
and enteric-coated salicylate
preparations are absorbed more slowly.
Food, antacids in the stomach delay
absorption.
Rectally : have a slower, more erratic
absorption.
Salicylates are distributed widely.
Pharmacodynamic
Reduce pain and reduce inflammation
by Inhibiting the synthesis of
prostaglandin.
Reduce fever by stimulating the
hypothalamus, producing dilation of
the peripheral blood vessels and
increased sweating.
Aspirin, permanently inhibits platelet
aggregation by interfering the
production of thromboxane A2
Pharmacotherapeutics
Salicylates are used primarily to relieve
pain and reduce fever, not effective to
relieve visceral pain or severe pain from
trauma.
Reduce inflammation in rheumatic fever,
rheumatoid arthritis, and osteoarthritis.
Relieve headache and muscle ache
Aspirin can be used to enhance blood flow
during myocardial infarction (MI) and to
prevent recurrence of MI (have Anticlotting
properties)
Side Effects
Gastric distress, Nausea, vomiting, and
bleeding tendencies.
Hearing loss (when taken for prolonged
periods)
Diarrhea, thirst, sweating, tinnitus,
confusion, dizziness, impaired vision,
and Hyperventilation (rapid breathing)
Reye’s syndrome (when given to children
with chickenpox or flulike symptoms).
Drug interactions
Oral anticoagulants, heparin,
methotrexate, oral antidiabetic agents, and
insulin are may have increase toxicity
Probenecid, sulfinpyrazone, and
spironolactone may have a decreased
effect
Corticosteroids may decrease plasma
salicylate levels and increase the risk of
ulcers.
Continue...
Alkalinizing drugs and antacids may
reduce salicylate levels.
The antihypertensive effect of ACEI and
beta blockers may be reduced.
NSAIDs may have a reduced therapeutic
effect and an increased risk of GI effects
Acetaminophen
Member of para -aminophenol
derivatives
Acetaminophen is absorbed rapidly
and completely from the GI tract, the
rectum.
Acetaminophen is distributed widely,
readily crosses the placental barrier.
Acetaminophen reduces pain and
fever, but it doesn’t affect
inflammation or platelet function
Pharmacotherapeutics
Acetaminophen is used to reduce
fever and relieve headache, muscle
ache, and general pain.
Effective pain reliever for some types
of arthritis
Drug interactions
The effects of oral anticoagulants and
thrombolytic drugs may be slightly
increased.
The risk of liver toxicity is increased
when combine with long-term alcohol
use, phenytoin, barbiturates,
carbamazepine, and isoniazid
The effects of lamotrigine, loop diuretics,
and zidovudine may be reduced
Nonsteroidal anti-inflammatory
drugs
Are typically used to combat
inflammation.
Have analgesic and antipyretic effects.
Effects of NSAIDs on platelet
aggregation are temporary.
Two Types of NSAIDs
There are : selective and nonselective.
The nonselective NSAIDs : diclofenac,
etodolac, fenoprofen, flurbiprofen,
ibuprofen, indomethacin, ketoprofen,
ketorolac, meloxicam, nabumetone,
naproxen, oxaprozin, piroxicam, and
sulindac.
The selective NSAID : celecoxib
Pharmacodynamics
Two isoenzymes of cyclooxygenase,
known as COX -1 and COX -2, convert
arachidonic acid into prostaglandins.
The nonselective NSAIDs block both
COX -1 and COX -2.
Selective NSAIDs block only the COX-2
enzyme.
Difference of Selective and Nonselective
NSAIDS
The prostaglandins produced by COX-1
maintain the stomach lining, while those
produced by COX-2 cause inflammation.
That’s why the nonselective NSAIDs (inhibit
COX -1and COX -2) commonly cause GI
adverse effects.
Selective NSAIDs alleviate pain and
inflammation without causing significant GI
adverse effects because they inhibit only
COX-2.
Pharmacotherepeutics
NSAIDs are used primarily to decrease
inflammation.
They’re secondarily used to relieve
pain.
Seldom prescribed to reduce fever.
Particularly useful in the treatment of
osteoarthritis, rheumatoid arthritis,
acute pain, primary dysmenorrhea,
and familial adenomatous polyposis.
Continue... favorably to treatment
Ankylosing spondylitis
Moderate to severe rheumatoid arthritis
Osteoarthritis
Acute gouty arthritis
Dysmenorrhea (painful menstruation)
Migraine headaches
Bursitis and tendonitis
Mild to moderate pain.
Side Effects
Abdominal pain, bleeding, anorexia,
diarrhea, nausea, ulcers, and liver
toxicity
Drowsiness, headache, dizziness,
confusion, tinnitus, vertigo, and
depression
Bladder infection, blood in the urine, and
kidney necrosis
Hypertension, heart failure, and pedal
edema.
Awareness
Patients considering the use of
celecoxib should be carefully screened
for a history of cerebrovascular or
cardiovascular disease.
Children: Some NSAIDs aren’t
recommended for use in children.
Elderly patients: The risk of ulcers
increases with age.
Continue...
Pregnant and breast -feeding women:
Diclofenac, flurbiprofen, ketoprofen, and
naproxen are pregnancy risk category B
drugs.
Etodolac, ketorolac, meloxicam,
nabumetone, oxaprozin, piroxicam ,
celecoxib are category C drugs.
Because most NSAIDs appear in breast
milk, it’s best not to use these drugs in
breast -feeding women.
Drug interactions
A wide variety of drugs can interact with NSAIDs,
especially with indomethacin, piroxicam, and
sulindac.
Such drugs as fluconazole, phenobarbital, rifampin,
ritonavir, and salicylates affect absorption of NSAIDs,
NSAIDs affect the absorption of such drugs as oral
anticoagulants, aminoglycosides, ACE inhibitors,
beta-adrenergic blockers, digoxin, dilantin, and
many others.
Decrease the clearance of lithium, which can result
in lithium toxicity.
Reduce the antihypertensive effects of ACE inhibitors
and diuretics.
Phenazopyridine hydrochloride
Produces a local analgesic effect on the urinary
tract is used to relieve such symptoms as
pain, buring, urgency, and frequency associated
with urinary tract infections.
Causing the patient’s urine to turn an orange or
red Color. The drug
If the drug accumulates the patient’s skin
and sclera may assume a yellow tinge stop
Acute renal or hepatic failure may occur.
Opioid Analgesics
Opioid agonists (also called narcotic
agonists) include opium derivatives and
synthetic drugs with similar properties.
They’re used to relieve or decrease pain
without causing the person to lose
consciousness.
Some opioid agonists also have
antitussive effects and antidiarrheal
actions.
Member of Opioids
codeine morphine sulfate
fentanyl (including morphine
sulfate sustained -
hydrocodone
release tablets and
hydromorphone intensified oral
levorphanol solution)
Petidine/meperidine oxycodone
methadone oxymorphone
propoxyphene
remifentanil
sufentanil.
Pharmacokinetis
Opioid agonists administered I.V.
provide the most rapid (almost
immediate) and reliable pain relief.
The subcutaneous and I.M. routes may
result in delayed absorption, especially
in patients with poor circulation.
It’s distributed widely throughout body
tissues.
Have a relatively low plasma protein -
binding capacity (30% to 35%).
Pharmacodynamics
Opioid agonists reduce pain by binding to
opiate receptor sites (mu receptors and N-
methyl-D-aspartate receptors) in the
peripheral nervous system and the CNS.
Drugs stimulate the opiate receptors
mimic the effects of endorphins
produces the therapeutic effects of
analgesia and cough suppression.
It also produces respiratory depression .
Continue...
Opioid agonists, especially morphine,
causes contraction of bladder and
ureter.
Slowing intestinal peristalsis
constipation
Causing blood vessels to dilate,
especially in the face, head, and neck
hypotension can occur.
Causing constriction of the bronchial
muscles
Pharmacotherapeutics
Opioid agonists are prescribed to relieve severe
pain in acute, chronic, and terminal illnesses.
Reducing anxiety before a patient receives
anesthesia
Sometimes prescribed to control diarrhea and
suppress coughing.
Morphine relieves shortness of breath in
patients with pulmonary edema and left-sided
heart failure by dilating peripheral blood
vessels and decreasing cardiac preload.
Drug interactions
increases respiratory depression when combine
with other drugs that also decrease respirations,
such as alcohol, sedatives, hypnotics, and
anesthetics,.
Severe constipation and urine retention when
combine with tricyclic antidepressants,
phenothiazines, or anticholinergics.
Drugs that may affect opioid analgesic activity
include amitriptyline, diazepam, phenytoin,
protease inhibitors, and rifampin.
Drugs that may be affected by opioid analgesics
include carbamazepine, warfarin, beta-
adrenergic blockers, and calcium channel
blockers.
Mixed opioid agonist-antagonists
Have agonist and antagonist properties.
The agonist component relieves pain, while the
antagonist component decreases the risk of
toxicity (respiratory depression) and drug
dependence.
Member of this groups:
Buprenorphine
Butorphanol
Nalbuphine
Pentazocine hydrochloride (combined with
pentazocine lactate, naloxone, aspirin, or
Acetaminophen).
Awareness
Patients who abuse opioids
shouldn’t receive mixed opioid
agonist-antagonists because these
drugs can cause symptoms of
withdrawal.
Mixed opioid agonist-antagonists
are listed as pregnancy risk c
Anesthetic drugs
Can be divided into three
groups’general anesthetics, local
anesthetics, and topical anesthetics.
General anesthetic drugs are further
subdivided into two main types:
those given by inhalation
those given intravenously.
Inhalation Anesthetics
Commonly used general anesthetics given by
inhalation include: desflurane, enflurane,
halothane, isoflurane, nitrous oxide,
sevoflurane.
Pharmacodynamics :
Inhalation anesthetics work primarily by
depressing the CNS producing loss of
consciousness, loss of responsiveness to
sensory stimulation (including pain), and
muscle relaxation.
Pharmacotherapeutics
Inhalation anesthetics are used for
surgery because they offer more
precise and rapid control of depth of
anesthesia than injection anesthetics
do.
Intravenous anesthetics
Member of this groups :
Barbiturates (methohexital, thiopental)
Benzodiazepines (midazolam)
Dissociatives (ketamine)
Hypnotics (etomidate, propofol)
Opiates (fentanyl, sufentanil).
Pharmacotherapeutics
It are typically used when the patient requires general
anesthesia for just a short period such as during
outpatient surgery.
Also used to promote rapid induction of anesthesia or
to supplement inhalation anesthetics.
Barbiturates are used alone in surgery that isn’t
expected to be painful and as adjuncts to other drugs
in more extensive procedures.
Benzodiazepines produce sedation and amnesia, but
not pain relief.
Etomidate is used to induce anesthesia and to
supplement low-potency inhalation anesthetics such
as nitrous oxide.
The opiates provide pain relief and supplement other
anesthetics.
Local anesthetics
Are administered to prevent or relieve pain
in a specific area of the body.
In addition, these drugs are often used as
an alternative to general anesthesia for
elderly or debilitated patients.
Amide anesthetics : bupivacaine,
lidocaine, mepivacaine, prilocaine,
ropivacaine.
Ester anesthetics : chloroprocaine,
procaine, tetracaine.
Pharmacodynamics
Local anesthetics block nerve impulses at the
point of contact in all kinds of nerves.
They accumulate causing the nerve cell
membrane to expand the cell loses its
ability to depolarize (impulse transmission)
Pharmacotherapeutics
Local anesthetics are used to prevent and
relieve pain from medical procedures, disease,
or injury.
Also be used for severe pain that topical
anesthetics or analgesics can’t relieve.
Combined ....
For some procedures, a local
anesthetic is combined with a drug
that constricts blood vessels, such as
epinephrine.
Vasoconstriction helps control local
bleeding and reduces absorption of
the anesthetic.
Reduced absorption prolongs the
anesthetic’s action at the site and
limits its distribution and CNS effects.
Topical anesthetics
It are applied directly to intact skin or
mucous membranes.
All topical anesthetics are used to
prevent or relieve minor pain.
Some injectable local anesthetics,
such as lidocaine and tetracaine, are
also topically effective.
Pharmacodynamics
Benzocaine, butacaine, cocaine,
dyclonine, and pramoxine produce
topical anesthesia by blocking nerve
impulse transmission.
Dibucaine, lidocaine, and tetracaine
may also block impulse transmission
across the nerve cell membranes.
continue...
Topical anesthetics produce little systemic
absorption, except for the application of cocaine to
mucous membranes. Systemic absorption may
occur in frequent or high -dose applications
Ethyl chloride spray superficially freezes the tissue,
stimulating the cold –sensation receptors and
blocking the nerve endings in the frozen area.
Menthol selectively stimulates the sensory nerve
endings for cold, causing a cool sensation and
some local pain relief.
Pharmacotherapeutics
Topical anesthetics are used to:
Relieve or prevent pain, especially minor burn
pain
Relieve itching and irritation
Anesthetize an area before an injection is given
Numb mucosal surfaces before a tube/urinary
catheter, is inserted
Alleviate sore throat or mouth pain when used
in a spray or solution.
Tetracaine is also used as a topical anesthetic
for the eye.
Benzocaine is used with other drugs in several
ear preparations.
WHO Analgesic step ladder
Step 1: Non opioid (+ or-) adjuvant
.(VAS 2- 4/10).
Step 2: Weak opioid (+) Non opioid (+
or-) adjuvant(VAS 4-6/10).
Step 3: Strong opioid(+) Non opioid (+
or-) adjuvant (VAS>6/10).
Step 4: Anesthetic/Neurosurgical
Interventions.
Hapalkan Dosis dan sediaan
berikut :
1. Parasetamol
2. Peroksikan
3. Na-diklofenak
4. Petidin
5. Morfin