Fentanyl. 2 mg. A lethal dose in most people. Diameter of a US penny is 19.05 mm, or 0.75 inches. Risk factors for<unk>  include<unk>  dependence, injecting<unk> s, using high doses of<unk> s, and use together with alcohol, benzodiazepines, or cocaine. The risk is particularly high following detoxification. Dependence on prescription<unk> s can occur from their use to treat chronic pain. In young children an overdose is usually due to<unk> s that are intended for their parents, older siblings, or grandparents. In mothers who take codeine during breastfeeding,<unk> s have occurred in their baby. Codeine is therefore not recommended in those who are breastfeeding. Co-ingestion<unk> s are often associated with benzodiazepines or alcohol use. Other CNS depressants, muscle relaxers, pain relievers, anti-convulsants, anxiolytics, treatment drugs of a psychoactive or epileptic variety or any other such drug with its active function meant to calm or mitigate neuronal signaling (barbiturates, etc.) can additionally cause a worsened condition with less likelihood of recovery cumulative to each added drug. This includes drugs less immediately classed to a slowing of the metabolism such as with GABAergic like GHB or glutamatergic antagonists like PCP or ketamine.
Opioid overdose
Stroke
Nicotine withdrawal
Alcohol intoxication
Benzodiazepine overdose
Hypoglycemia
Carbamate poisoning
Head injury