Drug/Small Molecule:

nitroglycerin

A volatile vasodilator which relieves angina pectoris by stimulating guanylate cyclase and lowering cytosolic calcium. PubChem (source: Drug Bank)

For the prevention of angina (source: Drug Bank)

Similar to other nitrites and organic nitrates, nitroglycerin is converted to nitric oxide (NO), an active intermediate compound which activates the enzyme guanylate cyclase. This stimulates the synthesis of cyclic guanosine 3',5'-monophosphate (cGMP) which then activates a series of protein kinase-dependent phosphorylations in the smooth muscle cells, eventually resulting in the dephosphorylation of the myosin light chain of the smooth muscle fiber. The subsequent release of calcium ions results in the relaxation of the smooth muscle cells and vasodilation. (source: Drug Bank)

Nitroglycerin, an organic nitrate, is available in many forms as a vasodilator. Nitroglycerin is used in the treatement of angina pectoris and perioperative hypertension, to produce controlled hypotension during surgical procedures, to treat hypertensive emergencies, and to treat congestive heart failure associated with myocardial infarction. (source: Drug Bank)

Avoid alcohol.
Dissolve under the tongue.
Take on empty stomach: 1 hour before or 2 hours after meals. (source: Drug Bank)

Hepatic, cytochrome P450 (P450) is a key enzyme of organic nitrate biotransformation (source: Drug Bank)

Increased intracranial pressure, with any or all of persistent throbbing headache, confusion, and moderate fever; Vertigo; Palpitations; Visual disturbances; Nausea and vomiting (possibly with colic and even bloody diarrhea); Syncope (especially in the upright posture); Air hunger and dyspnea, later followed by reduced ventilatory effort; Diaphoresis, with the skin either flushed or cold and clammy; Heart block and bradycardia; Paralysis; Coma; Seizures; Death. (source: Drug Bank)

C(C(CON(=O)=O)ON(=O)=O)ON(=O)=O (source: Drug Bank)