Morphine, formerly known as morphium, is an opiate found naturally in opium, a dark brown resin produced by drying the latex of opium poppies (Papaver somniferum). It is mainly used as an analgesic (pain medication). There are multiple methods used to administer morphine: oral; sublingual; via inhalation; injection into a muscle, injection under the skin, or injection into the spinal cord area; transdermal; intravenously; or via rectal suppository. It acts directly on the central nervous system (CNS) to induce analgesia and alter perception and emotional response to pain. Physical and psychological dependence and tolerance may develop with repeated administration. Long-acting formulations of morphine are sold under the brand names MS Contin and Kadian, among others. Generic long-acting formulations are also available.
Common side effects of morphine include drowsiness, euphoria, nausea, dizziness, sweating, and constipation. This is believed to be the first isolation of a medicinal alkaloid from a plant. Merck began marketing it commercially in 1827.
The primary source of morphine is isolation from poppy straw of the opium poppy. In 2013, approximately 523 tons of morphine were produced. About 70% of morphine is used to make other opioids such as hydromorphone, oxymorphone, and heroin. It is a Schedule II drug in the United States, and Schedule I in Canada. It is on the World Health Organization's List of Essential Medicines. In 2023, it was the 156th most commonly prescribed medication in the United States, with more than 3million prescriptions. It is available as a generic medication.
Medical uses
Pain
Morphine is used primarily to treat both acute and chronic severe pain. Its duration of analgesia is about three to seven hours.
Morphine has also traditionally been used in the treatment of acute pulmonary edema.
A 2016 Cochrane review concluded that morphine is effective in relieving cancer pain.
Shortness of breath
Morphine is beneficial in reducing the symptom of shortness of breath due to both cancer and non-cancer causes. In the setting of breathlessness at rest or on minimal exertion from conditions such as advanced cancer or end-stage cardiorespiratory diseases, regular, low-dose sustained-release morphine significantly reduces breathlessness safely, with its benefits maintained over time.
Opioid use disorder
Morphine is used in a slow-release formulation for opiate substitution therapy (OST) in Austria, Germany, Bulgaria, Slovenia, and Canada for persons with opioid addiction who cannot tolerate either methadone or buprenorphine.
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File:GT-Capros-Morphinsulfat-2018.jpg|Two capsules (5 mg & 10 mg) of morphine sulfate extended-release
File:Morphine 1mL Vial.jpg|1 milliliter ampoule containing 10 mg of morphine
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Contraindications
Relative contraindications to morphine include:
- Respiratory depression when appropriate equipment is not available.