Which of the following is incorrect with reference to drug abuse?

The correct answer is Option (3) → Nicotine is a very effective sedative and pain killer.

Option (1) Cannabinoids affect cardiovascular system of the body. — A correct statement. Cannabinoids come from Cannabis sativa (marijuana, hashish, charas, ganja). They are known for their effects on the heart and blood vessels.

Option (2) Heroin is extracted from the latex of Papaver somniferum. — A correct statement. Morphine is taken from the latex of the poppy plant, and heroin is made from morphine by acetylation. So heroin traces back to the poppy latex.

Option (3) Nicotine is a very effective sedative and pain killer. — An incorrect statement. Nicotine is an alkaloid in tobacco. It is a stimulant: it makes the adrenal gland release adrenaline and noradrenaline, which raise blood pressure and heart rate. The effective sedative and painkiller is morphine.

Option (4) Excessive dosage of coca alkaloid causes hallucinations. — A correct statement. Cocaine (coca alkaloid) comes from Erythroxylum coca. It interferes with dopamine transport, and too much of it causes hallucinations.

NCERT Extract:
Drugs and Alcohol Abuse – “Drugs like barbiturates, amphetamines, benzodiazepines, and other similar drugs, that are normally used as medicines to help patients cope with mental illnesses like depression and insomnia, are often abused. Morphine is a very effective sedative and painkiller, and is very useful in patients who have undergone surgery.”