Drug Index

C₉H₈O₄180.2 g/mol

Acetylsalicylic acid — one of the most widely used medications in history. Irreversibly inhibits cyclooxygenase (COX) enzymes, reducing pain, inflammation, and fever. Low-dose aspirin prevents blood clots by suppressing thromboxane A₂.

C₁₃H₁₈O₂206.3 g/mol

A propionic acid derivative NSAID (non-steroidal anti-inflammatory drug). Reversibly inhibits COX-1 and COX-2. Exists as R and S enantiomers — only S-(+)-ibuprofen is pharmacologically active, but the body converts R to S.

C₈H₉NO₂151.2 g/mol

Paracetamol (Tylenol) — a widely used analgesic and antipyretic. Unlike NSAIDs, it has minimal anti-inflammatory activity. Overdose causes fatal liver damage through toxic metabolite NAPQI accumulation.

C₈H₁₀N₄O₂194.2 g/mol

The world's most widely consumed psychoactive substance. A purine alkaloid that blocks adenosine receptors, promoting wakefulness. Found in coffee (~95 mg/cup), tea (~45 mg/cup), and chocolate. Half-life ~5 hours in humans.

C₁₇H₁₉NO₃285.3 g/mol

The prototypical opioid analgesic, isolated from opium poppy in 1804. Acts on μ-opioid receptors in the brain and spinal cord. Named after Morpheus, the Greek god of dreams. Still a cornerstone of severe pain management.

C₄H₁₁N₅129.2 g/mol

The most widely prescribed oral diabetes medication (~150 million prescriptions/year). A biguanide that reduces hepatic glucose production and improves insulin sensitivity. Under investigation for anti-aging and anti-cancer properties.

C₁₆H₁₈N₂O₅S350.4 g/mol

An oral penicillin antibiotic. Contains the β-lactam ring that inhibits bacterial cell wall synthesis. Alexander Fleming's 1928 discovery of penicillin launched the antibiotic era and won the 1945 Nobel Prize.

C₂₁H₃₀O₂314.5 g/mol

THC — the principal psychoactive constituent of cannabis. Activates CB₁ receptors in the brain affecting mood, memory, and pain perception. Medicinally used for nausea, chronic pain, and appetite stimulation.

C₁₀H₁₄N₂162.2 g/mol

The primary addictive compound in tobacco. A nicotinic acetylcholine receptor agonist that triggers dopamine release. Acts as both a stimulant and relaxant depending on dose. Named after Jean Nicot, who introduced tobacco to France.

C₁₄H₂₂N₂O234.3 g/mol

The most widely used local anesthetic. Blocks voltage-gated sodium channels, preventing nerve impulse transmission. Also used as an antiarrhythmic drug (Class Ib). Available as injections, topical creams, and dental cartridges.

C₁₆H₁₃ClN₂O284.7 g/mol

Valium — a benzodiazepine that enhances GABA receptor activity, producing sedative, anxiolytic, muscle relaxant, and anticonvulsant effects. One of the most prescribed medications of the 20th century. Risk of dependence with long-term use.

C₁₇H₁₉N₃O₃S345.4 g/mol

The first proton pump inhibitor (PPI), irreversibly blocking gastric H⁺/K⁺-ATPase to reduce stomach acid production by up to 99%. Revolutionized treatment of peptic ulcers and GERD. One of the most prescribed drugs worldwide.

C₂₂H₂₃ClN₂O₂382.9 g/mol

A second-generation antihistamine (Claritin) that blocks H₁ receptors without crossing the blood-brain barrier significantly, causing minimal drowsiness. Used for allergic rhinitis and urticaria. Available over the counter worldwide.

C₂₂H₃₀N₆O₄S474.6 g/mol

Viagra — a PDE5 inhibitor originally developed for angina. Increases cGMP levels, causing smooth muscle relaxation and vasodilation. Revolutionized treatment of erectile dysfunction. Also approved for pulmonary arterial hypertension (as Revatio).