of buprenorphine/naloxone is generally prescribed to deter injection, since naloxone, an opioid antagonist, causes acute withdrawal if the formulation is crushed and injected. However, taken orally, the nalaxone has virtually no effect, due to the drug's extremely high first-pass metabolism and low bioavailability (2%). Before starting buprenorphine, individuals are generally advised to wait long enough after their last dose of opioid until they have some withdrawal symptoms to allow for the medication to bind the receptors, since if taken too soon, buprenorphine can displace other opioids bound to the receptors and precipitate an acute withdrawal. The dose of buprenorphine is then adjusted until symptoms improve, and individuals remain on a maintenance dose of 8–16 mg. Because withdrawal is uncomfortable and a deterrent for many patients, many have begun to call for different means of treatment initiation. Some providers have begun to use the Bernese method, also known as microdosing, in which very small doses of buprenorphine are given while patients are still using street opioids, and without precipitating withdrawal, with medicine levels slowly titrated upward. Buprenorphine versus methadone Both buprenorphine and methadone are medications used for detoxification and opioid replacement therapy, and appear to have similar effectiveness based on limited data. Both are safe for pregnant women with opioid use disorder, although preliminary evidence suggests that methadone is more likely to cause neonatal abstinence syndrome. In the US and European Union, only designated clinics can prescribe methadone for opioid use disorder, requiring patients to travel to the clinic daily. If patients are drug free for a period they may be permitted to receive "take home doses," reducing their visits to as little as once a week. Alternatively, up to a month's supply of buprenorphine has been able to be prescribed by clinicians in the US or Europe who have completed a basic training (8–24 hours in the US) and received a waiver/licence allowing prescription of the medicine. In France, buprenorphine prescription for opioid use disorder has been permitted without any special training or restrictions since 1995, resulting in treatment of approximately ten times more patients per year with buprenorphine than with methadone in the following decade. In 2021, seeking to address record levels of opioid overdose, the United States also removed the requirement for a special waiver for prescribing physicians. Whether this change will be sufficient to impact prescription is unclear, since even before the change as many as half