pain killeres

Card 1: Aspirin & Salicylates

Class: Non-Steroidal Anti-Inflammatory Drug (NSAID)

Mechanism of Action: Inhibits cyclooxygenase (COX) enzymes, leading to reduced prostaglandin synthesis.

Therapeutic Uses: Mild pain (Step 1 on WHO Pain Ladder).

High-Yield Side Effects & Toxins:

Peptic Ulcer & Bleeding: Gastrointestinal mucosal injury and prolonged bleeding time.

Reye's Syndrome: Severe brain and liver damage when given to children under 2 years old with a viral infection.

Salicylism (Toxicity): Features fever, bleeding, tinnitus/hearing loss, hallucinations, hyperventilation/increased respiratory rate, tachycardia, hypotension, convulsions, and coma.

Card 2: Morphine

Class: Natural Opioid Agonist

Mechanism of Action:

Agonist at (mu), (kappa), and (delta) G-protein coupled receptors.

Opens post-synaptic K^+ channels➡ hyperpolarization (decreases neuronal excitability).

Closes pre-synaptic voltage-gated Ca^{2+} channels➡decreases excitatory neurotransmitter release (e.g., Substance P in dorsal horn).

Pharmacological Effects:

CNS: Analgesia (spinal & supraspinal), euphoria, drowsiness, pin-point pupils (severe miosis via Edinger-Westphal nucleus stimulation), respiratory center depression, cough suppression, nausea/vomiting (via CTZ stimulation).

CVS & Smooth Muscle: Orthostatic hypotension (vasomotor center depression & histamine release), peripheral bronchospasm, sphincter contraction causing constipation, urinary retention, and biliary pressure increase.

Endocrine: Decreases LH, FSH, and ACTH levels \rightarrow loss of libido, impotence, and menstrual irregularities.

Therapeutic Uses: Severe pain (burns, trauma, post-op, terminal cancer), pre-anesthetic medication, epidural/intrathecal segmental analgesia, and relief of anxiety in acute myocardial infarction or severe internal bleeding.

Contraindications:

Obstetrics: Avoid during labor (causes fetal neonatal asphyxia due to immature blood-brain barrier).

Abdominal Pain: Contraindicated in acute undiagnosed abdomen and diagnosed biliary colic/renal colic (causes sphincter contraction).

Head Injury: Contraindicated due to increased intracranial pressure/respiratory depression.

Organ Failure: Severe hepatic or renal failure.

High-Yield Board Facts:

Non-Tolerated Side Effects: Patients develop tolerance to analgesia, euphoria, sedation, and respiratory depression, but NO tolerance develops to miosis and constipation.

Withdrawal: Autonomic hyperactivity (lacrimation, rhinorrhea, sweating, dilated pupils, diarrhea, hyperpyrexia) and muscle/joint aches.

Overdose Triad: Respiratory depression + Pin-point pupils + Coma (plus hypothermia & hypotension). Treat with Naloxone.

Card 3: Codeine

Class: Natural Opioid Agonist

Mechanism of Action: Low-potency \mu-receptor agonist. Prodrug that requires metabolic conversion (approx. 10%) into morphine for analgesic activity.

Therapeutic Uses: Mild to moderate pain, powerful selective cough suppressant (antitussive), and diarrhea treatment.

High-Yield Board Facts: Significantly lower potency, efficacy, addiction potential, and withdrawal severity compared to morphine.

Card 4: Meperidine (Pethidine)

Class: Synthetic Opioid Agonist

Mechanism of Action: Synthetic(kappa) agonist.

Therapeutic Uses:

Labor Analgesia: Preferred because it does not suppress fetal respiration like morphine.

Colic Pain: Indicated for severe renal and biliary colic because it acts as a smooth muscle relaxant.

High-Yield Board Facts:

Not used for cough or diarrhea.

Less potent than morphine but more potent than codeine.

Causes rapid dependence and short withdrawal symptoms.

Card 5: Tramadol

Class: Synthetic Codeine Analog / Dual-Action Analgesic

Mechanism of Action: Weak \mu-receptor agonist AND blocks reuptake of Norepinephrine (NE) and Serotonin (5-HT) in the CNS

Therapeutic Uses: Mild to moderate visceral pain (diagnostic procedures, injury, surgery).

Contraindications & High-Yield Toxicity:

SSRI Therapy: Strictly contraindicated with SSRIs due to the risk of triggering Serotonin Syndrome.

6.Fentanyl

Synthetic  μ  agonist,  with  80  times  higher  analgesic  effect  & respiratory depression than morphine, used in anesthesia.

 Because  of  high  lipid  solubility,  it  enters  brain  rapidly  and produces peak analgesia in 5 min after i.v. injection.

 The duration of action is short- 30–40 min

 Transdermal  fentanyl  has  become  available  for  use  in  cancer/ terminal illness or other types of chronic pain for patients requiring opioid analgesia.

Transdermal fentanyl patches are approved in sustained pain.

Rectal administration

Oral  transmucosal  administration:  Fentanyl  in  a  dissolvable  sugar- based lollipop or rapidly dissolving buccal tablet have been approved for the treatment of cancer pain Trans-nasal administration

7.Methadone

Slow tolerance & less physical dependence with mild withdrawal symptoms

 Used for treatment of opioid abstinence (withdrawal) syndrome

 Produces long QT syndrome: potentially fatal adverse effect OPIOID ANTAGONIST Naloxone

 Pure opioid antagonist used to treat respiratory depression in opioid toxicity

 Cause withdrawal symptoms in addicts CHRONIC PAIN: ROUTES OF ADMINISTRATION OF OPIATES

Spinal delivery: Administration of opioids into the epidural or intrathecal space

تجميعات

-A patient came into the ER with lacrimation, increased heart rate, sweating

and dilated pupils. Which drug is used to manage his condition?

A. Naloxon

B. Morphine

C. Opioid

D. Methadone

Answer: D

-.A 50 year old man is having sleep apnea and he wants to take an opioid for

his severe back pain. Which of the side effects will likely occur?

A. Respiratory depression

Answer: A

1. A pregnant woman in labour who previously had biliary colic. What analgesic should be given for her labour?

A. Meperidine

Answer: A

2. A patient came in the ER with lacrimation, increase heart rate, sweating and dilated pupils. Which drug is used to manage his condition?

A. Naloxone

B. Morphine

C. Opioid

D. Methadone

Answer: D

3. Which one of the following drugs is used during labor?

A. Methadone

B. Morphine

C. Meperidine

D. Opioid

Answer: C

4. Which one of the following is used during anesthesia?

A. Fentanyl

B. Tramadol

C. Meperidine

D. Opioid

Answer: A

5. A 20-year-old patient came to the ER with respiratory distress, pin-point pupil, hypothermia and hypotension. What’s the drug of choice to treat him?

A. Morphine

B. Meperidine

C. Codeine

D. Naloxone

Answer: D

الصيغة الاصلية:

Morphine poisoning antidote?

A. Naloxone

Answer: A

6. A 30-year-old woman is undergoing labour, Which of the following analgesic drugs is suitable for her?

A. Morphine

B. Codeine

C. Fentanyl

D. Meperidine

Answer: D

الصيغة الاصلية:

During labour an anesthetic drug is given

A. Meperidine

Answer: A