Brand Name: Buprenex, Carpuject, Simbadol, Zorbium

Available as injectable but usually prescribed as an oral spray, liquid, or applied as a long-acting topical.

Buprenorphine is a controlled substance. Specific paperwork is necessary for its prescription. 

Background

Opiates have been used since ancient times for their pain-relieving and euphoric properties. Neurologic studies have revealed brain receptors that bind opiates, each type of receptor responsible for different opiate effects. These receptors are named for the Greek letters mu, kappa, delta, and sigma. The mu receptor is responsible for the narcotic effects of euphoria, pain relief, addiction, lowering of heart rate, and respiratory depression. Buprenorphine is partially active at the mu receptor.

Buprenorphine is best used for mild to moderate pain, while stronger opiates are needed for deeper or more intensely painful conditions. Buprenorphine is a good choice for pain management after the patient is stable enough to return home.

How This Medication Is Used

This drug can be used as an injectable in the hospital setting but can also be used at home for pain control as an oral drop or spray especially for a cats. Buprenorphine is absorbed directly from the oral tissues (swallowing is not necessary) so a small amount of buprenorphine can be squirted in the cheek pouch. This is typically done 2-3 times daily with larger amounts lasting longer than smaller amounts. This method of administration is generally believed to work better in cats than dogs.

A newer product for cats (Zorbium®) employs a top-spot format. It is applied in the hospital and provides four days of pain relief from a single application. This product is available for cats between 2.6 lbs and 16.5 lbs and is meant for pain relief at home following surgical procedures. Since the dose is administered in the hospital, the convenience of this product is especially attractive.

Side Effects

• Approximately 2/3 of people using this medication experienced drowsiness. Pets may have a similar experience.
• Any narcotic has potential to reduce body temperature so the patient may need to be kept warm.
• Buprenorphine can cause a drop in heart rate as well as in blood pressure.
• Because respiratory depression is a possible side effect, buprenorphine should not be used in patients with respiratory compromise, including respiratory compromise from heart failure or head trauma. Respiratory depression from buprenorphine would be unusual in normal patients.
• Buprenorphine is removed from the body through the liver. Patients with liver disease will have prolonged effects.
• Naloxone can be used to reverse the side effects of this or any other narcotic.

Interactions With Other Drugs

The sedation side effect is more severe if this medication is used in conjunction with other medications that have a sedating side effect, including antihistamines.

Buprenorphine should not be used with selegiline or any other monoamine oxidase inhibitor because a potentially dangerous blood pressure situation called serotonin syndrome can result. A two-week waiting period is recommended if buprenorphine or any other narcotic is to be used in a patient on such a drug (usually a dog with canine cognitive dysfunction taking seligiline). Other compounds that could be problematic in this way include tick control products containing amitraz or the pain reliever tramadol.

The following drugs can increase blood levels of buprenorphine: ketoconazole, itraconazole, fluconazole (all antifungals), and erythromycin (an antibacterial antibiotic).

Concerns and Cautions

Buprenorphine should be stored at room temperature and protected from light exposure.

Buprenorphine definitely crosses the placenta to the unborn young and is secreted in the mother's milk, possibly in a concentrated form. It is thus best not used in pregnancy or lactation.

Opiates should be used with caution in patients with hypothyroidism, hypoadrenocorticism, or who are generally debilitated.

Transmucosal delivery of buprenorphine in cats is as reliable as injection, but in dogs, only about 50 percent of the buprenorphine is absorbed into the body from the mouth. This route might still be useful if dose adjustments are taken into consideration.

In 2014, a veterinary-labeled product called Simbadol® was released. This product is for cats only and is injectable only. The buprenorphine in Simbadol® has been treated so that one dose can be expected to last for 24 hours. This version of buprenorphine cannot be used orally.

If you skip a dose by accident, do not double up on the next dose. Instead, simply pick up at the next dose as normal.