Which of the following alkaloids is a potent constipating agent?

The initial stage of drug addiction is

Many secondary metabolites of plants have medicinal properties. It is their misuse that creates problems. Justify the statement with an example.

Which side effects are observed in females due to the use of anabolic steroids?

Those who take drugs intravenously (direct injection into the vein using a needle and syringe),are much more likely to acquire serious infections like?

Match the following pairs:

Column $I$ (Type of addiction)	Column $II$ (Organ/system affected)
$i$. Heroin	$a$. Increases neurotransmitter dopamine
$ii$. Marijuana	$b$. Cardiovascular system
$iii$. Cocaine	$c$. Liver cirrhosis
$iv$. Alcohol	$d$. Gastrointestinal tract

Select the correct option from the following.