Methadone is a long-acting, synthetic, narcotic drug that was first used in the maintenance treatment of drug addiction in the 1960s. It is an opiate "agonist," which means that it acts in a way that is similar to morphine and other narcotic medications.
When used in proper doses in maintenance treatment, methadone does not create euphoria, sedation, or an analgesic effect. Doses must be individually determined based on a person's body weight and opiate tolerance. The proper maintenance dose is the one at which the cravings stop, without creating effects of euphoria or sedation.
Although methadone is not a single product from a single manufacturer, the active ingredient is always the same: methadone hydrochloride. All manufacturers add a small number of additional inactive ingredients, such as magnesium steurate and cellulose. Some of the US companies that manufacture methadone include cherry or orange flavoring. Methadone is dispensed orally in different forms, which include tablets, powder, and liquid. For most people, a single dose of methadone lasts 24 to 36 hours.
How is methadone different from heroin and other opioids?
Methadone lasts longer. The body metabolizes methadone differently than it does heroin or morphine. When a person takes methadone regularly, it builds up and is stored in the body, so it lasts even longer when used for maintenance. Most people find that once they're stabilized on a dose of methadone that is right for them, a single oral dose will "hold" them for at least a full 24-hour day. For some, the effect lasts longer and for others a shorter time.
Stability is easier on oral methadone. Most people who are on a stable, appropriate does of methadone for several weeks will not feel any significant sense of being "high" or "dopesick." Some patients may feel a "transition" or a temporary mild glow for a short time several hours after being medicated, however. Others may feel slightly "dopesick" prior to taking the day's medication, but most will feel very little or no effect from the proper dose of methadone once they have stabilized.