The anesthetic sodium thiopental has been in the news recently because there is a shortage of it in this country. This has brought some media attention because it is the first in a three-drug protocol for capital punishment. It seems that there is no longer any American manufacturer, and manufacturers in other countries will only import it if they are guaranteed that it won’t be used in lethal injections. The Food and Drug Administration (FDA) has declined to approve importation, and the Drug Enforcement Agency (DEA) is investigating whether current prison supplies were obtained legally. It turns out that the protocol to use this drug is very old, and there is not much data available on whether or not the dosage works as intended—to put the prisoner to sleep. Unfortunately, the drug happens to also be used by anesthesiologists in certain kinds of patients who cannot take the usual anesthetics.

Sodium thiopental is an anesthetic that is given first in the three-drug protocol for lethal injection. It is supposed to induce sleep. The second is pancuronium bromide, used to induce muscle paralysis. The third is potassium chloride, which causes cardiac arrest. This protocol was first developed by an anesthesiologist in the 1930s as an alternative to electrocution or cyanide gas. The protocol was based on his experience and has been used ever since. A PLoS Medicine (Public Library of Science) 2007:4(4) study, sought to find data on executions in prisons around the country. From the limited data available, it was found that time of death varied from five to forty-five minutes, and that there were eyewitness accounts of problematic executions, with some prisoners’ eyes open, mouths moving, or seizures occurring until time of death. Furthermore, the dosage of sodium thiopental varied from 0.1 to 2 times LD50 (lethal dose). It was concluded that the sodium thiopental may not always have induced a surgical plane of anesthesia and some prisoners may have died from respiratory arrest from the pancuronium chloride, rather than from cardiac arrest from the potassium chloride.

Sodium thiopental is FDA-approved for veterinary use in this country, as well as for use by anesthesiologists for those patients who can’t take the usual anesthetics, such as geriatric and obstetric patients, and those with certain cardiac and neurological conditions. The inability to obtain this drug could cause problems in the treatment of these patients.

Some prisons have been scrambling to come up with alternatives to sodium thiopental since it looks like this drug won’t be available after current supplies are used up. Oklahoma has tried pentobarbital, a more readily available drug that is sometimes used to treat epilepsy. The states of Ohio and Texas have followed suit, and several other states are considering the switch. The problem is that changing the protocol involves a bit of legal red tape to get through, and it can delay the process for several months or longer. Though Pentobarbital is widely used in veterinary medicine, its analgesic effects in humans are not well-defined. It is a sedative often used in epilepsy and it is manufactured in this country.

This all started when the Italian government refused to allow Hospira, Inc. (the sole US manufacturer of Pentothal® or thiopental sodium) to export thiopental unless the company could guarantee the government that the drug would not be used in lethal injections. Since Hospira, Inc. couldn’t make that promise, it decided to get out of that market. No other American company makes this drug. Of the thirty-five states with capital punishment, sodium thiopental is used in thirt-four of them. Prisons in California, Arizona, Georgia, Arkansas and Tennessee subsequently tried to procure the drug from an English firm, but this firm’s legality was questionable. (The firm’s address was the same as that of a driving school in a dodgy London neighborhood.) It was at this point that the DEA stepped in to investigate whether the importation of sodium thiopental was being done according to US law. Sodium thiopental is a controlled substance and it is thus the responsibility of the DEA to regulate its importation and sale. The agency confiscated Georgia’s supply and has also been investigating in Kentucky and Tennessee. Separately, the state of Nebraska had tried to obtain thiopental from an Indian source, but India also objected to the potential use of the drug for capital punishment; they subsequently declined to sell.

The problem comes down to the fact that there is no way for manufacturers to control the end destination of the drug, and how it will be used when it gets there. In cases where prisons and hospitals have asked the FDA for help in obtaining the drug, the FDA stated that this was outside their mission and that they “could not approve a drug for harm.” In the meantime, prisons have been buying the drug from other prisons and hospitals in the United States (but they are still required to register the purchase with the DEA).