Morphine has also traditionally been used in the treatment of acute pulmonary edema. A 2006 review, though, found little evidence to support this practice. 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 noncancer 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 also available as 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. Contraindications
Relative contraindications to morphine include:

respiratory depression when appropriate equipment is not available. Although it has previously been thought that morphine was contraindicated in acute pancreatitis, a review of the literature shows no evidence for this. Adverse effects
Constipation
Like loperamide and other opioids, morphine acts on the myenteric plexus in the intestinal tract, reducing gut motility, causing constipation. The gastrointestinal effects of morphine are mediated primarily by μ-opioid receptors in the bowel. By inhibiting gastric emptying and reducing propulsive peristalsis of the intestine, morphine decreases the rate of intestinal transit. Reduction in gut secretion and increased intestinal fluid absorption also contribute to the constipating effect. Opioids also may act on the gut indirectly through tonic gut spasms after inhibition of nitric oxide generation.
Closely related to morphine are the opioids morphine-N-oxide (genomorphine), which is a pharmaceutical that is no longer in common use; and pseudomorphine, an alkaloid that exists in opium, form as degradation products of morphine.As a result of the extensive study and use of this molecule, more than 250 morphine derivatives (also counting codeine and related drugs) have been developed since the last quarter of the 19th century. These drugs range from 25% the analgesic strength of codeine (or slightly more than 2% of the strength of morphine) to several thousand times the strength of morphine, to powerful opioid antagonists, including naloxone (Narcan), naltrexone (Trexan), diprenorphine (M5050, the reversing agent for the Immobilon dart) and nalorphine (Nalline). Some opioid agonist-antagonists, partial agonists, and inverse agonists are also derived from morphine. The receptor-activation profile of the semi-synthetic morphine derivatives varies widely and some, like apomorphine are devoid of narcotic effects. Salts
Both morphine and its hydrated form are sparingly soluble in water. For this reason, pharmaceutical companies produce sulfate and hydrochloride salts of the drug, both of which are over 300 times more water-soluble than their parent molecule. Whereas the pH of a saturated morphine hydrate solution is 8.5, the salts are acidic.