[Editor's Note: This is the third and final part in a series chronicalling William Burroughs search for an opiod cure, and the veterinary pharmaceuticals he came into contact with during his journey.]

Read Part One.

Read Part Two.

Phenothiazines:

The phenothiazines, a family of drugs with similar molecular structure capable of inducing sedation, act centrally in the brain. Initially they found use in human medicine as antipsychotics. Their popularity among the medical establishment during the period of Burrough's opiate addiction probably explains his encounter with them. Namely, it was chlorpromazine (thorazine) that Burroughs used, noting some benefit during opiate withdrawal, but commenting that the drug was fraught with side effects: "depression, disturbances of vision, indigestion" among them.

The veterinary practitioner will be most familiar with acepromazine, although other phenothiazine derivatives including chlorpromazine and fluphenazine have fallen in and out of favor over recent years. Acepromazine is frequently used as an aid in controlling fractious animals. The yellow, viscous solution is a potent sedative although many mild side effects are associated with the drug. Without fail, the most frequently publicized is the agent's propensity to induce penile relaxation in the gelding or stallion. The penile retractor muscles and associated nerves responsible for placement of the penis within the sheath are thought to be under sole influence of alpha-adrenergic stimulation. Since acepromazine acts as an alpha-adrenergic blocker, it is capable of paralyzing the penis in a relaxed, extended state. The penis, in this position, is vulnerable to blunt trauma and the effects of gravity, which favor blood pooling, and occasionally, marked swelling. The breeding stud is dependent upon this organ to earn his livelihood, and in this respect, inappropriate use of acepromazine in the stallion can be a career ending event.

Fluphenazine (Prolixen(r)), a long acting phenothiazine derivative, has not been widely adopted by the veterinary community. Nevertheless, it has found a somewhat nefarious role in the sport horse industry. Trainers have used the drug to dull a poorly behaved horse before a sale or to "take the edge off" an excitable racehorse. The four to six week duration of action of the drug, extrapolated from the human literature, seems to suit these less than moral applications. However, side effects and adverse reactions are common with fluphenazine, due in no small part to the lack of consensus over what constitutes an appropriate dose in the horse. How an individual suddenly finding himself in possession of fluphenazine may decide upon a dose is an interesting question, although I suspect that basic arithmetic forms no part of the answer. The adverse reaction experienced by some horses under the influence of fluphenazine is characteristic of human Parkinsonism: rhythmic muscle tremors, rigidity, restlessness and agitation. I have witnessed a single case of fluphenazine toxicity in an equine patient. The horse spent large portions of the day either weight bearing upon its haunches, in a dogsitting position, or flexed at the knees with its hindquarters elevated, like a massive praying mantis. Although this horse spent hours, trancelike, in these positions, it should be noted that neither of these postures is ever adopted by any horse within the scope of normal, irrespective of how broadly normality is defined. Prey animals aren't afforded the luxury of looking foolish.

Dissociatives:

Although Burroughs never utilized these drugs, they deserve an honorable mention, for they approach the euphoria he sought in opiates but carry little addictive potential. The most well known of the class is ketamine, due largely to its recent popularity with the street culture. Drugs in this class disrupt pathways in the central nervous system, effectively dissociating mind from body. At sufficient doses, they are extraordinarily effective and versatile general anesthetics, used commonly in veterinary practice. Within the scope of a single week, I've used ketamine to anesthetize llamas for castration, spay barn cats on a kitchen table, and drop a horse for exploratory abdominal surgery. Their propensity to induce significant muscle rigidity -- manifest in the cat by an appearance of extreme rigor mortis -- requires that they be administered with a muscle relaxant, such as Valium(r) or guaifenesin.

Telazol(r), a combination of tiletamine, a dissociative, and zolazepam, a muscle relaxant similar to Valium(r), has found wide use amongst wildlife professionals for anesthesia and restraint of short duration. The product comes bundled, somewhat like software, by the pharmaceutical company. Recently, I had the opportunity to observe the use of this product on a leopard in the Namibian bush. Just outside of Otjiwarongo, not far from the Angolan border, the Cheetah Conservation Foundation had baited one of its resident leopards into a 12x5x10-foot chain link enclosure. The leopard was to receive dental care -- a crown fitted to a fractured canine -- from a dentist nearly an hour away by dirt track. The veterinarian I had accompanied -- a tall, lanky bush pilot of British descent named Mark -- was to dart the leopard, transport him in the bed of his pickup, and maintain him under anesthesia until release. The procedure would require multiple "top up" doses of Telazol(r) to sustain anesthetic depth.

Under a cloudless African sky, we milled about, behind the dubious safety of several parked Land Cruisers, and observed as the leopard paced the length of the cage. Mark meticulously loaded his air rifle and flanked the cage behind a giant baobab. The leopard became a blur of fury as it threw itself, irate, in his direction, stopped short only by the chain fence. Mark turned toward us, "I think he's pissed," he said flatly. Perhaps we should have loaded the dart with more Telazol(r) I thought, and hoped Mark could hit muscle. Shortly, we would be dragging this leopard out of the enclosure, and it occurred to me then that he probably didn't fracture the tooth grooming himself. Tracking the rhythmic pacing, Mark raised the rifle to his shoulder, and the report rang out. The leopard's rage with being hit degenerated to a hiss as he sank to the ground, sedate.

It's not clear that Burroughs would have played with special K the way that those in possession of the stolen drug do today. But he considered it. Months before his death in 1997, Burroughs, ever the intrepid explorer, toyed with the idea of taking ketamine as a means of approximating the near-death experience. In the end, he decided against it, fearing that in his failing health, the drug might itself precipitate his death.

It can be difficult for the casual observer to understand the scope of opiate addiction. What is the experience of total need? Junk, Burroughs noted, is not a way of life, as though, for the junkie, there is some other. Junk is the only way of life. When one considers that the junkie willingly pursues treatment involving drugs that can bring an eighteen hundred pound Belgian draft horse to its knees, the scope becomes astonishingly clear. Thiopental, thorazine, reserpine. Wouldn't you?