💠 Orlistat is an anti-obesity medication, not an ADHD drug.

💠 It inhibits gastric and pancreatic lipase, preventing fat absorption in the intestines.

💠 Main effects: oily stool, flatulence, steatorrhea, and fat-soluble vitamin loss.

💠 Used alongside diet and exercise for sustainable weight management.

💠 ADHD, by contrast, is treated with stimulants (methylphenidate, amphetamines) or atomoxetine.

🔷 Serotonin syndrome results from excess serotonergic activity in the CNS.

🔷 Clinical triad: neuromuscular hyperactivity, mental status changes, autonomic instability.

🔷 Key findings: tremor, clonus, hyperreflexia, agitation, diaphoresis, fever.

🔷 Often triggered by combining SSRI + MAOI, triptans, or linezolid.

🔷 Treated by stopping serotonergic drugs, giving benzodiazepines or cyproheptadine.

⭐ Half-life (t½) means time needed for 50% of the drug to be eliminated.

⭐ After one t½ (5 hours), 800 mg → 400 mg remains.

⭐ After two t½ → 200 mg; after three → 100 mg, etc.

⭐ Follows first-order kinetics, where rate of elimination ∝ concentration.

⭐ Knowing t½ helps predict dosing intervals and steady state (4–5 t½).

🟣 Phase I trials use healthy volunteers to test safety and pharmacokinetics.

🟣 Objectives: assess absorption, distribution, metabolism, excretion, and dose tolerance.

🟣 Establishes starting dose range and identifies side effects.

🟣 Phase II–III test efficacy and safety in patients; Phase IV monitors post-marketing effects.

🟣 Phase I provides the foundation for future trial design.

💠 Definition: NMS is a life-threatening neurological emergency caused by the body’s reaction to dopamine receptor blockade, especially from antipsychotic medications.

💠 Clinical Triad: The classic presentation includes severe hyperthermia, “lead-pipe” muscle rigidity, and autonomic dysfunction (fluctuating BP, tachycardia).

💠 Pathophysiology: Occurs due to sudden, profound dopamine depletion in the CNS, particularly within the hypothalamus and basal ganglia.

💠 Laboratory Findings: Elevated creatine kinase (CK) and myoglobinuria indicate muscle breakdown (rhabdomyolysis).

💠 Management: Immediate discontinuation of the antipsychotic, supportive care, and administration of dantrolene or bromocriptine to restore dopaminergic activity.

🔷 Mechanism: Naloxone is a pure opioid receptor antagonist, especially at mu-opioid receptors, reversing respiratory and CNS depression rapidly.

🔷 Administration: Can be given IV, IM, SQ, or intranasally, depending on the setting, and acts within 1–2 minutes after IV injection.

🔷 Indications: Used in acute opioid overdose, commonly for heroin, morphine, fentanyl, oxycodone, or mixed-drug overdoses involving opioids.

🔷 Duration: Has a short half-life (30–90 minutes), so repeat doses or continuous infusion may be required for long-acting opioids.

🔷 Caution: It can precipitate acute withdrawal symptoms (agitation, tachycardia, vomiting) in opioid-dependent individuals, but the benefit outweighs the risk.

♦ Mechanism: Levodopa is a dopamine precursor that crosses the blood–brain barrier, where it is decarboxylated into dopamine, compensating for the deficiency in Parkinson’s.

♦ Purpose: Restores dopaminergic transmission in the basal ganglia, improving control over motor function.

♦ Combination Therapy: Usually administered with carbidopa, which inhibits peripheral metabolism of levodopa, allowing more to reach the brain and reducing side effects like nausea.

♦ Clinical Benefit: Improves bradykinesia, rigidity, and tremor, enhancing mobility and daily functioning.

♦ Adverse Effects: May cause dyskinesias, orthostatic hypotension, and hallucinations after prolonged use due to fluctuating dopamine levels.

🟢 Generic Definition: The generic name is the official, non-proprietary name assigned to a drug, recognized internationally (e.g., acetaminophen).

🟢 Trade Definition: The trade (brand) name is the commercial name chosen by a pharmaceutical company (e.g., Tylenol).

🟢 Cost Difference: Generic drugs are typically less expensive because they lack marketing costs and are produced after patent expiry.

🟢 Chemical Identity: Both names refer to the same active ingredient, meaning efficacy and safety are therapeutically equivalent when FDA-approved.

🟢 Labeling: Nurses should use generic names in documentation to avoid confusion, since trade names can differ across countries and manufacturers.