Butorphanol is a synthetic opioid agonist-antagonist analgesic with a pharmacological and therapeutic profile that has been well established since its launch as a parenteral formulation in 1978. The introduction of a transnasal formulation of butorphanol represents a new and noninvasive presentation of an analgesic for moderate to severe pain. This route of administration bypasses the gastrointestinal tract, and this is an advantage for a drug such as butorphanol that undergoes significant first-pass metabolism after oral administration. The onset of action and systemic bioavailability of butorphanol following transnasal delivery are similar to those after parenteral administration. Butorphanol blocks pain impulses at specific sites in the brain and spinal cord.

Butorphanol:
https://drugs.ncats.io/drug/QV897JC36D

Butorphanol is a synthetic opioid which is used as a nasal spray for treatment of migraine headaches and parenterally as a narcotic analgesic for moderate-to-severe pain or as an adjunct to general anesthesia. The partial agonist-antagonist activity of butorphanol causes it to antagonize the effects of fully agonist opioids such as morphine and fentanyl, and higher doses of butorphanol do not provide the euphoria typical of full agonists. Butorphanol was first approved for use in the United States in 1978. It remains available as a solution for injection as well as nasal spray (typically for migraine headaches). Indications for the parenteral forms of butorphanol include moderate-to-severe pain that is not responsive to nonnarcotic analgesia. Butorphanol is available generically and previously under the brand names Stadol as a solution for injection and nasal spray in concentrations of 10 mg/mL.

Butorphanol has a lower potential for physical and psychological dependency than morphine, fentanyl and oxycodone and is classified as a Schedule IV drug, indicating that it has medical usefulness, and only a low potential for physical and psychological dependency and abuse.

Liver:
Butorphanol has not been linked to serum enzyme elevations during therapy or to clinically apparent liver injury.

Butorphanol Hepatotoxicity:
Therapy with butorphanol has not been linked to serum enzyme elevations during therapy or to instances of idiosyncratic, clinically apparent liver injury. It is generally given for short periods of time for acute pain only and experience with prolonged use is limited.

Butorphanol Overview:
https://www.ncbi.nlm.nih.gov/books/NBK547902/

Butorphanol is a synthetic opioid with mixed agonist/antagonist properties. It is analgesic with a potency 3 to 5 times greater than that of morphine in humans. Butorphanol provides analgesia and mild sedation but does not cause respiratory depression unless high dose rates are used. Butorphanol is used for mild-to-moderate pain and seems to be more effective for visceral pain than musculoskeletal pain.

ScieneDirect Animal Medications:
https://www.sciencedirect.com/topics/veterinary-science-and-veterinary-medicine/butorphanol

Breastfeeding:

Summary of Use During Lactation:
Limited data indicate that butorphanol is excreted into breastmilk in small amounts.

Butorphanol is poorly orally absorbed, so it is unlikely to adversely affect the breastfed infant.

However, because there is no published experience with repeated, high, intravenous or intranasal doses of butorphanol during breastfeeding, other agents may be preferred in these situations, especially while nursing a newborn or preterm infant.

Monitor the infant for drowsiness, adequate weight gain, and developmental milestones, especially in younger, exclusively breastfed infants.

As with other narcotics, once the mother's milk comes in, it is best to limit maternal intake and to supplement analgesia with a nonnarcotic analgesic if necessary for pain control.

If the baby shows signs of increased sleepiness (more than usual), difficulty breastfeeding, breathing difficulties, or limpness, a physician should be contacted immediately.

Labor pain medication may delay the onset of lactation.

Drug Levels:
In adults, the oral bioavailability of butorphanol is 17% while the intranasal bioavailability is 70%. Butorphanol is metabolized to inactive metabolites.

Intranasal and parenteral doses of 25 to 30 mcg/kg have been used in infants as young as 6 months for postoperative analgesia.

Effects on Lactation and Breastmilk:

Narcotics and narcotic agonist-antagonists can increase serum prolactin.

However, the prolactin level in a mother with established lactation may not affect her ability to breastfeed.

Alternate Drugs to Consider:

• Acetaminophen
• Hydromorphone
• Ibuprofen
• Morphine
• Nalbuphine

Butorphanol Drug Levels and Effects:
https://www.ncbi.nlm.nih.gov/books/NBK501203/

Stadol (butorphanol tartrate)

Side Effects:
Get emergency medical help if you have signs of an allergic reaction: hives; difficulty breathing; swelling of your face, lips, tongue, or throat.
RxList
Stadol (butorphanol tartrate): https://www.rxlist.com/stadol-drug/patient-images-side-effects.htm
Opioid medicine can slow or stop your breathing, and death may occur. A person caring for you should seek emergency medical attention if you have slow breathing with long pauses, blue colored lips, or if you are hard to wake up.
Call your doctor at once if you have: noisy breathing, sighing, shallow breathing, breathing that stops during sleep a slow heart rate or weak pulse fast or pounding heartbeats problems with urination a light-headed feeling, like you might pass out confusion, feeling like you are floating
Seek medical attention right away if you have symptoms of serotonin syndrome, such as: agitation, hallucinations, fever, sweating, shivering, fast heart rate, muscle stiffness, twitching, loss of coordination, nausea, vomiting, or diarrhea.
Serious side effects may be more likely in older adults and those who are overweight, malnourished, or debilitated.
Common side effects include: nausea, vomiting drowsiness, dizziness dry mouth warmth or redness under the skin
This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

Butorphanol Tartate, commonly known as Torbugesic, Torbutrol or Dolorex, is primarily used in dogs and cats for pain relief and for coughing. Butorphanol belongs to a general class of drugs known as opiate agonists. Other related drugs in this class include buprenorphine, fentanyl, meperidine and morphine. The drug has significant pain control and sedation properties but does not last long.

This drug is registered for use in animals and humans. Human formulations: Stadol (Mead Johnson). Veterinary formulations: Torbugesic (Fort Dodge), Dolorex (Merck) and Torbutrol (Fort Dodge).

Excerpt from petplace.com:
https://www.petplace.com/article/drug-library/drug-library/library/butorphanol-tartrate-torbugesic-torbutrol-dolorex-for-dogs-and-cats/

Pediatric:
Appropriate studies have not been performed on the relationship of age to the effects of butorphanol nasal spray in the pediatric population.

Safety and efficacy have not been established.

Geriatric:
Appropriate studies performed to date have not demonstrated geriatric-specific problems that would limit the usefulness of butorphanol nasal spray in the elderly. However, elderly patients may be more sensitive to the effects of this medicine than younger adults, and are more likely to have age-related liver, kidney, heart, or lung problems, which may require caution and an adjustment in the dose for patients receiving butorphanol nasal spray.

Other Interactions:

• Ethanol

Other Medical Problems:
Make sure you tell your doctor if you have any other medical problems, especially:

• Adrenal problems
• Alcohol abuse, history of
• Brain tumor, history of
• Breathing problems (eg, chronic obstructive pulmonary disease [COPD], cor pulmonale, hypoxia)
• Drug dependence, especially narcotic abuse or dependence, or history of
• Head injuries, history of
• Heart attack, history of
• Heart or blood vessel problems
• Increased pressure in the head
• Seizures, history of
• Weakened physical condition - Use with caution. May increase risk for more serious side effects

• Gallbladder disease
• Hypertension (high blood pressure)
• Hypotension (low blood pressure)
• Pancreatitis (inflammation or swelling of the pancreas), acute - Use with caution. May make these conditions worse

• Kidney disease
• Liver disease - Use with caution. The effects may be increased because of slower removal of the medicine from the body

• Lung or breathing problems, severe (eg, bronchial asthma, respiratory depression)
• Stomach or bowel blockage (including paralytic ileus), known or suspected - Should not be used in patients with these conditions

Butorphanol (Nasal Route) (Stadol NS):
https://www.mayoclinic.org/drugs-supplements/butorphanol-nasal-route/description/drg-20074007

World Health Organization 2006:

Other names:

• Butorfanol Tartrate

Trade names:

• Alvegesic
• APO-Butorphanol
• Beforol
• Butorject
• Butomidor
• Butormidor
• Butorphanol
• Butorphanol Tartrate
• Butrum
• Dolorex
• Equanol
• LIN-Butorphanol NS
• Moradol
• Morphasol
• PMS-Butorphanol
• Repressor-E
• Spofa
• Stadol
• Stadol FM
• Stadol NS
• Stadol NS 7
• Torate
• Torbugesic
• Torbutrol
• Verstadol FM
• Vetus Trajectory

World Health Organization Butorphanol Critical Review Report (PDF 25 pages):
https://www.who.int/medicines/areas/quality_safety/4.1ButhorphanolCritReview.pdf

Erowid Experience Vault:
https://erowid.org/experiences/subs/exp_Pharms_Butorphanol.shtml

Butorphanol Tartrate Nasal Solution

Maximum Dosage:
Prescribers Digital Reference
Butorphanol Tartrate Nasal Solution - Drug Summary: https://www.pdr.net/drug-summary/Butorphanol-Tartrate-Nasal-Solution-butorphanol-tartrate-1959
Adults:	The maximum dosage is dependent on route of administration and indication for therapy.
Elderly	The maximum dosage is dependent on route of administration and indication for therapy.
Adolescents:	Safety and efficacy have not been established.
Children:	Safety and efficacy have not been established.

FDA Stadol Medication Guide (PDF 25 pages):
https://www.accessdata.fda.gov/drugsatfda_docs/label/2002/19890s17lbl.pdf

Important Information:
MISUSE OF OPIOID MEDICINE CAN CAUSE ADDICTION, OVERDOSE, OR DEATH. Keep the medication in a place where others cannot get to it.

Using butorphanol during pregnancy may cause life-threatening withdrawal symptoms in the newborn.

Fatal side effects can occur if you use this medicine with alcohol, or with other drugs that cause drowsiness or slow your breathing.

Do not drink alcohol. Dangerous side effects or death could occur.

Avoid driving or hazardous activity until you know how butorphanol will affect you. Dizziness or drowsiness can cause falls, accidents, or severe injuries.

Interactions:

Drug Interactions (482) Alcohol/Food Interactions (2) Disease Interactions (17)

What other drugs will affect Butorphanol?
You may have breathing problems or withdrawal symptoms if you start or stop taking certain other medicines. Tell your doctor if you also use an antibiotic, antifungal medication, heart or blood pressure medication, seizure medication, or medicine to treat HIV or hepatitis C. Opioid medication can interact with many other drugs and cause dangerous side effects or death. Be sure your doctor knows if you also use:

• other narcotic medications - opioid pain medicine or prescription cough medicine
• a sedative like:
  • Valium - diazepam
  • alprazolam
  • lorazepam
  • Xanax
  • Klonopin
  • Ativan
  • others
• drugs that make you sleepy or slow your breathing - a sleeping pill, muscle relaxer, medicine to treat mood disorders or mental illness
• drugs that affect serotonin levels in your body - a stimulant, or medicine for depression, Parkinson's disease, migraine headaches, serious infections, or nausea and vomiting

This list is not complete. Other drugs may affect butorphanol, including prescription and over-the-counter medicines, vitamins, and herbal products. Not all possible interactions are listed here.

A total of 482 drugs are known to interact with Butorphanol.

• 186 major drug interactions
• 295 moderate drug interactions
• 1 minor drug interactions

Butorphanol Drug Information:
https://www.drugs.com/mtm/butorphanol-nasal.html

Drugs.com: Butorphanol Tartrate Monograph https://www.drugs.com/monograph/butorphanol-tartrate.html

European Medicines Agency Butorphanol Tartrate Summary Report (PDF 4 pages):
https://www.ema.europa.eu/en/documents/mrl-report/butorphanol-tartrate-summary-report-committee-veterinary-medicinal-products_en.pdf

US National Library of Medicine Dailymed Dolorex Drug Label Info:
https://dailymed.nlm.nih.gov/dailymed/drugInfo.cfm?setid=3c274f98-94db-4674-ac28-69d683db4842

http://www.dolorex.info

Its tradename Stadol was recently discontinued by the manufacturer. It is now only available in its generic formulations

Butorphanol:

• A synthetic opioid analgesic
• Structurally related to levorphanol
• Patented in 1971
• Approved for medical use in 1979
• The most common indication for butorphanol is management of migraine using the intranasal spray formulation
• It may also be used parenterally for management of moderate-to-severe pain, as a supplement for balanced general anesthesia, and management of pain during labor.
• It is also quite effective at reducing post-operative shivering (owing to its Kappa agonist activity)

Butorphanol is more effective in reducing pain in women than in men

• In veterinary anesthesia, butorphanol (trade name: Torbugesic) is widely used as a sedative and analgesic in dogs, cats and horses.
• It is also prohibited for use in competition by most equestrian organizations, including the FEI, which considers it a class A drug.

As with other opioid analgesics, central nervous system effects (such as sedation, confusion, and dizziness) are considerations with butorphanol.

Butorphanol is available as the tartrate salt in injectable, tablet, and intranasal spray formulations. The tablet form is only used in dogs, cats and horses due to low bioavailability in humans.