In the 1850s, Alexander Wood reported that he had injected morphine into his wife Rebecca as an experiment; the myth goes that this killed her because of respiratory depression, but she outlived her husband by ten years.Later it was found that morphine was more addictive than either alcohol or opium, and its extensive use during the American Civil War allegedly resulted in over 400,000 people with the "soldiers disease" of morphine addiction. This idea has been a subject of controversy, as there have been suggestions that such a disease was in fact a fabrication; the first documented use of the phrase "soldiers disease" was in 1915.Diacetylmorphine (better known as heroin) was synthesized from morphine in 1874 and brought to market by Bayer in 1898. Heroin is approximately 1.5 to 2 times more potent than morphine weight for weight. Due to the lipid solubility of diacetylmorphine, it can cross the blood–brain barrier faster than morphine, subsequently increasing the reinforcing component of addiction. Using a variety of subjective and objective measures, one study estimated the relative potency of heroin to morphine administered intravenously to post-addicts to be 1.80–2.66 mg of morphine sulfate to 1 mg of diamorphine hydrochloride (heroin). Morphine became a controlled substance in the US under the Harrison Narcotics Tax Act of 1914, and possession without a prescription in the US is a criminal offense. Morphine was the most commonly abused narcotic analgesic in the world until heroin was synthesized and came into use.
An idioventricular rhythm is a cardiac rhythm characterized by a rate of <50 beats per minute (bpm), absence of P waves and widening of the QRS complex. In cases where the heart rate is  between 50 and 110 bpm, it is known as accelerated idioventricular rhythm and ventricular tachycardia if the rate exceeds 120 bpm. Causes of idioventricular rhythms are varied and can include drugs or a heart defect at birth. It is typically benign and not life-threatening. Etiology
Various etiologies may contribute to the formation of an idioventricular rhythm, and include:
Heart block
Reperfusion after myocardial infarction
Electrolyte abnormalities
Heart diseases present at birth
Certain drugs (eg. digoxin, β-agonists, anaesthetics)

Pathophysiology
The physiological pacemaker of the heart is the sinoatrial node. If the sinoatrial node is rendered dysfunctional, the AV node may act as the pacemaker. If both of these fail, the ventricles begin to act as the dominant pacemaker in the heart. The ventricles acting as their own pacemaker gives rise to an idioventricular rhythm. Diagnosis
An ECG trace is required for diagnosis. Treatment
As this rhythm is not life-threatening, treatment has limited value for the patient. If underlying pathologies are identified, they should be treated appropriately. Antidysrhythmics may be utilised if the patient suffers from dysrhythmias. == References ==