Last reviewed 2026-04-20 · How we verify

Belladonna and Opium

Belladonna/opium rectal suppository combines atropine and morphine to relax smooth muscles and increase pain threshold, respectively.

Belladonna and Opium is a marketed rectal suppository developed by the University of Washington, primarily indicated for ureteral spasm pain management. The combination of atropine and morphine provides a dual mechanism of action, effectively relaxing smooth muscles and increasing the pain threshold, which is a key competitive advantage. The primary risk is the key composition patent expiry in 2028, which could lead to increased competition from generics.

At a glance

Mechanism of action

This drug works by using atropine to relax smooth muscles in the body, which helps reduce spasms. Morphine, on the other hand, increases the body's pain threshold and reduces sensitivity to pain, providing analgesic effects. Atropine also counteracts any smooth muscle spasms caused by morphine without reducing its pain-relieving properties.

Approved indications

• Ureteral Spasm Pain Management

Boxed warnings

• WARNING: ADDICTION, ABOUSE, AND MISUSE; LIFE-THREATENING RESPIRATORY DEPRESSION; ACCIDENTAL EXPOSURE; NEONATAL OPIOD WITHDRAWAL SYNDROME; and RISKS FROM CONCOMITANT USE WITH ALCOHOL, BENZODIAZEPINES OR OTHER CNS DEPRESSANTS Addiction, Abuse, and Misuse Belladonna and opium suppositories expose patients and other users to the risks of opioid addiction, abuse, and misuse, which can lead to overdose and death. Assess each patient’s risk prior to prescribing belladonna and opium suppositories, and monitor all patients regularly for the development of these behaviors or conditions [ see Warnings and Precautions (5.1) ]. Life-Threatening Respiratory Depression Serious, life-threatening, or fatal respiratory depression may occur with use of belladonna and opium suppositories. Monitor for respiratory depression, especially during initiation of belladonna and opium suppositories or following a dose increase [ see Warnings and Precautions (5.2) ]. Accidental Exposure Accidental exposure of even one dose of belladonna and opium suppositories, especially by children, can result in a fatal overdose of opium [ see Warnings and Precautions (5.2) ]. Neonatal Opioid Withdrawal Syndrome Prolonged use of belladonna and opium suppositories during pregnancy can result in neonatal opioid withdrawal syndrome, which may be life-threatening if not recognized and treated, and requires management according to protocols developed by neonatology experts. If opioid use is required for a prolonged period in a pregnant woman, advise the patient of the risk of neonatal opioid withdrawal syndrome and ensure that appropriate treatment will be available [ see Warnings and Precautions (5.3) ]. Risks From Concomitant Use With Alcohol, Benzodiazepines Or Other CNS Depressants Concomitant use of opioids with benzodiazepines or other central nervous system (CNS) depressants, including alcohol, may result in profound sedation, respiratory depression, coma, and death [ see Warnings and Precautions (5.4), Drug Interactions (7) ]. • Reserve concomitant prescribing of belladonna and opium suppositories and benzodiazepines or other CNS depressants for use in patients for whom alternative treatment options are inadequate. • Limit dosages and durations to the minimum required. • Follow patients for signs and symptoms of respiratory depression and sedation WARNING: ADDICTION, ABOUSE, AND MISUSE; LIFE-THREATENING RESPIRATORY DEPRESSION; ACCIDENTAL EXPOSURE; NEONATAL OPIOD WITHDRAWAL SYNDROME; and RISKS FROM CONCOMITANT USE WITH ALCOHOL, BENZODIAZEPINES OR OTHER CNS DEPRESSANTS See full prescribing information for complete boxed warning. • Belladonna and opium suppositories expose users to risks of opioid addiction, abuse, and misuse, which can lead to overdose and death. Assess patient’s risk before prescribing and monitor regularly for these behaviors or conditions. (5.1) • Serious, life-threatening, or fatal respiratory depression may occur. Monitor closely, especially upon initiation or following a dose increase. (5.2) • Accidental exposure of belladonna and opium suppositories, especially by children, can result in a fatal overdose of opium. (5.2) • Prolonged use of belladonna and opium suppositories during pregnancy can result in neonatal opioid withdrawal syndrome, which may be life-threatening if not recognized and treated. If prolonged opioid use is required in a pregnant woman, advise the patient of the risk of neonatal opioid withdrawal syndrome and ensure that appropriate treatment will be available. (5.3) • Concomitant use of opioids with benzodiazepines or other central nervous system (CNS) depressants, including alcohol, may result in profound sedation, respiratory depression, coma, and death. Reserve concomitant prescribing for use in patients for whom alternative treatment options are inadequate; limit dosages and durations to the minimum required; and follow patients for signs and symptoms of respiratory depression and sedation. (5.4, 7)

Common side effects

• Drowsiness
• Dry mouth
• Urinary retention
• Photophobia
• Rapid pulse
• Dizziness
• Blurred vision
• Constipation
• Nausea
• Vomiting
• Pruritis
• Urticaria

Serious adverse events

• Serotonin syndrome
• Adrenal insufficiency
• Anaphylaxis
• Androgen deficiency
• Life-threatening respiratory depression
• Neonatal opioid withdrawal syndrome
• Severe hypotension
• Seizures
• Withdrawal
• Hypersensitivity

Drug interactions

• Alcohol, Benzodiazepines and Other Central Nervous System (CNS) Depressants
• Serotonergic Drugs
• Monoamine Oxidase Inhibitors (MAOIs)
• Mixed Agonist/Antagonist and Partial Agonist Opioid Analgesics
• Muscle Relaxants

Key clinical trials

• The Use of Belladonna and Opium Suppository in the Treatment of Postoperative Stent Pain (PHASE4)
• Effects of Perioperative B&O Suppositories on Post-op Pain and Morphine Use After Laparoscopic Prostatectomy (NA)
• B&O for TLH Post-operative Pain and Nausea (PHASE4)
• Timing of B and O Suppositories to Help Relieve Post-operative Bladder Spasms (PHASE4)
• Assessing Maternal Post-partum Pain With Suppositories (PHASE4)
• Effect of an Anti-spasmodic Suppository to Improve Comfort After Urologic Surgery (NA)
• Postoperative Belladonna and Morphine Suppositories in Vaginal Surgery (PHASE4)

Primary sources

Every claim on this page is sourced from regulatory or scientific primary sources. See our editorial policy for full methodology.

Competitive intelligence

For the full competitive landscape — auto-detected comparators, recent regulatory actions across the set, upcoming PDUFA, patent timeline, sponsor landscape:

• Belladonna and Opium CI brief — competitive landscape report
• Belladonna and Opium updates RSS · CI watch RSS
• University of Washington portfolio CI