Main article: Drug overdose
Overdose is a method of suicide which involves taking medication in doses greater than the indicated levels, or in a combination that will interact to either cause harmful effects or increase the potency of one or other of the substances.[citation needed]
An overdose is the preferred method of dignified dying among members of right-to-die societies. A poll among members of right-to-die society Exit International has shown that 89% would prefer to take a pill, rather than use a plastic exit bag, a CO generator, or use 'slow euthanasia'.[62]
Reliability of this method highly depends on chosen drugs and additional measures like use of antiemetics to prevent vomiting. Average fatality rate for overdoses in the US is estimated to be only 1.8%.[63] At the same time, assisted suicide group Dignitas reported no single failure among 840 cases (fatality rate 100%), where an overdose of a former sleeping pill active agent Nembutal was used in combination with antiemetic drugs.[64]
While barbiturates (such as Seconal or Nembutal) have long been an option for suicide, they are becoming increasingly difficult for potential suicide victims to acquire. Dutch right-to-die society WOZZ proposed several safe alternatives to barbiturates for use in euthanasia.[65] The Peaceful Pill Handbook suggests the still easy availability of solutions containing pentobarbital in Mexico, where they are available over-the-counter from veterinarians for animal euthanasia.
A typical drug overdose uses random prescription and over-the-counter substances. In this case, death is uncertain, and an attempt may leave a person alive but with severe organ damage, although that itself may in turn eventually prove fatal. Drugs taken orally may also be vomited back out before being absorbed. Considering the very high doses needed, vomiting or losing consciousness before taking enough of the active agent is often a major problem for people attempting this.[citation needed]
Analgesic overdose attempts are among the most common, due to easy availability of over-the-counter substances.[66] Overdose may also be achieved by mixing medications in a cocktail with one another, or with alcohol or illegal drugs. This method may leave confusion over whether the death was a suicide or accidental, especially when alcohol or other judgment-impairing substances are also involved and no suicide note was left behind.