Morphine Medication DescriptionMorphine is a pain medication of the opiate family which is found naturally in a number of plants and animals, including humans. It acts directly on the central nervous system to decrease the feeling of pain. It can be taken for both acute pain and chronic pain. Wikipedia Formula: C₁₇H₁₉NO₃ IUPAC ID: (4R,4aR,7S,7aR,12bS)-3-methyl-2,4,4a,7,7a,13-hexahydro-1H-4,12-methanobenzofuro[3,2-e]isoquinoline-7,9-diol Bioavailability: 20–40% (by mouth), 36–71% (rectally), 100% (IV/IM) Duration of action: 3–7 hours Onset of action: 5 minutes (IV), 15 minutes (IM), 20 minutes (PO) Excretion: Renal 90%, biliary 10% Drug class: opioid