Xylazine

Xylazine is an analogue of clonidine and an agonist at the α2 class of adrenergic receptor. It is used for sedation, anesthesia, muscle relaxation, and analgesia in animals such as horses, cattle and other non-human mammals. Veterinarians also use xylazine as an emetic, especially in cats. Xylazine is an analogue of clonidine and an agonist at the α2 class of adrenergic receptor. It is used for sedation, anesthesia, muscle relaxation, and analgesia in animals such as horses, cattle and other non-human mammals. Veterinarians also use xylazine as an emetic, especially in cats. In veterinary anesthesia, xylazine is often used in combination with ketamine. It is sold under many brand names worldwide, most notably the Bayer brand name Rompun. It is also marketed as Anased, Sedazine, and Chanazine. The drug interactions vary with different animals. It has become a drug of abuse, particularly in Puerto Rico, where it is diverted from stocks used by equine veterinarians and used as a cutting agent for heroin. Xylazine is often used as a sedative, muscle relaxant, and analgesic. It is frequently used in the treatment of tetanus. Xylazine is very similar to drugs such as phenothiazine, tricyclic antidepressants, and clonidine. As an anesthetic, it is typically used in conjunction with ketamine. Xylazine appears to reduce sensitivity to insulin and glucose uptake in humans. Yohimbine has been used to decrease glucose levels to a healthy level. In clinical settings, Yohimbine can reverse the adverse effects of xylazine if administered intravenously at a dosage of 0.5 mL / 20 pounds shortly after xylazine administration. Xylazine overdose is usually fatal in humans. Because it is used as a drug adulterant, the symptoms caused by the drugs accompanying xylazine administration vary between individuals. The most common side effects in humans associated with xylazine administration include bradycardia, respiratory depression, hypotension, transient hypertension secondary to vagus nerve stimulation, and other changes in cardiac output. Xylazine significantly decreases heart rate in animals that are not premedicated with medications that have anticholinergic effects. The decrease in heart rate directly impacts aortic flow. Bradycardia caused by xylazine administration is effectively prevented by administration of atropine or glycopyrrolate. Arrhythmias associated with xylazine includes other symptoms such as sinoatrial block, atrioventricular block, A-V dissociation, and sinus arrhythmia. Xylazine administration can lead to diabetes mellitus and hyperglycemia. Other possible side effects that can occur are areflexia, asthenia, ataxia, blurred vision, disorientation, dizziness, drowsiness, dysarthria, dysmetria, fainting, hyporeflexia, slurred speech, somnolence, staggering, coma, apnea, shallow breathing, sleepiness, premature ventricular contraction, tachycardia, miosis, and dry mouth. Rarely, hypotonia, dry mouth, urinary incontinence and nonspecific electrocardiographic ST segment changes occur. It has been reported that the duration of symptoms after human overdose is 8 to 72 hours. Further research is necessary to categorize the side effects that occur when xylazine is used in conjunction with heroin and cocaine. Chronic use is reported to be associated with physical deterioration, dependence, abscesses, and skin ulceration, which can be physically debilitating and painful. Hypertension followed by hypotension, bradycardia, and respiratory depression lower tissue oxygenation in the skin. Thus, chronic use of xylazine can progress the skin oxygenation deficit, leading to severe skin ulceration. Lower skin oxygenation is associated with impaired healing of wounds and a higher chance of infection. The ulcers may have a characteristic odor and ooze pus. In severe cases, amputations must be performed on the affected extremities. The known doses of xylazine that produce toxicity and fatality in humans vary from 40 to 2400 mg. Small doses may produce toxicity and larger doses may be survived with medical assistance. Non-fatal blood or plasma concentration ranges from 0.03 to 4.6 mg/L. In fatalities, the blood concentration of xylazine ranges from trace to 16 mg/L. It is reported that there is no defined safe or fatal concentration of xylazine because of the significant overlap between the non-fatal and postmortem blood concentrations of xylazine.