Addictive drugs can be categorized into 4 types according to their impact on addicted persons.

1. Sedatives: This type will temporarily cause dizziness, nerve anesthesia, drowsiness and loss of self. Addictive drugs in this type are

1.1 Opium which is made from the latex of the opium poppy which is boiled until it is black. Cooked opium tastes bitter, has a rank odor and is easily dissolved in water. Opium can be consumed in many ways.

The health impacts of opium - result from an alkaloid which sedates the brain and causes dizziness, insensitiveness towards cold and hot, unawareness of body pain, being bored with food, getting constipated, being unhealthy and catching infections easily.

Withdrawal symptoms - are moodiness, excitedness, unrest, yawning, tear secretion, body pain and bloody defecation.

1.2 Heroine is chemically produced from the opium morphine. Its chemical name is Diacetylmorphine. 2 types of heroin are in use.

- Pure heroin is a white powder and has a bitter taste.

- Mixed heroin is a brown, pink, yellow or violet powder. Heroin is often mixed with arsenic, strychnine, sleeping pills, quinine etc.

The health impact of heroin - is same as that of opium but 30-100 times more severe. Heroin is consumed by injection or inhalation.

1.3 Sleeping pills are barbiturates which are derivatives of the barbituric acid. They are available as fast or slow activating drugs called secobarbital or seconal. Among drug users the names commonly used are blue and yellow Natalie, Lhao-Hang, Kai-Dang or Pisard-Dang. They are sold as white pills or colorful blue, red etc capsules.

Health impact of sleeping pill: Sleeping pills will depress the central nervous system. If taken in an overdose, drug users might develop speech disorder, shaking walk become moody, might be hurting themselves and start disputing. When deprived of the drugs, drug users might shiver, be anxious, feel nauseous or have hallucination.

2. Stimulants: a person who takes these drugs will become nervous and wide awake. After the effects of the drug diminish, the drug addict will be exhausted because of lack of rest. The drugs in this class are as follow.

2.1 Kratom is a perennial plant. It looks like Ylang-ylang (Kradang-nga Thai) but the ribs of the leaf are red. The alkaloid derived from Kratom is called mitragynine.

Health impacts of mitragynine: It will stimulate the drug addict, induce happiness, create the impression of being powerful, suppress hunger and withstand sunshine for long hours. However, they might develop fear of rain, become constipated, become unhealthy and may cause mental disorder.

2.2 Amphetamine (Ya Ba or Ya Ma): It is a stimulating drug. It is sold as white tablets, red tablets, and capsules or as powder. It will be taken by eating or mixed with drinks.

Health impacts of amphetamine: It might increase the heart beat, raise blood pressure, induce hyperventilation, dry lips and shaking hands and make the user talkative. If drug addicts take amphetamines for a long time, they will be weak, have their muscles exhausted, brain and nerves degenerated, become confused and hallucinate. These effects will cause drug addicts to become mentally disordered, mad and unable control themselves. When trying to stop the drug abuse, the withdrawal symptoms will be severe.

2.3 Tranquilizers: They are not considered to be addictive drugs but may cause dependency when the drug is taken regularly in an increased dose. The drugs’ impacts can be diagnosed as light, as caused by Diazepam, or as severe, as caused by Chlorpromazine and Hydrazine whose trade names are Latagtin, Lemlalil etc.

Health impacts of tranquilizers: These drugs will help not to be worried, moody and saddened. But if a patient takes them in overdose, it may affect the brain and nervous system.

3. Hallucinogens: This class of drugs will cause hallucinations, visual and auditoryillusions, and disorientation. Users might not be able to control themselves anymore which may lead to death. These drugs are as follows:

3.1 Volatile substances are classified as organic chemicals with a unique odor such as benzene, thinner, kerosene, super glue, LSD, melatonin, and psilocybin mushrooms etc.

Health impacts of volatile substances: they depress the central nervous system which causes brain disorder, giddiness, and blurred eyes, loss of appetite, hepatitis and liver malfunction. If drug addicts sniff it too much, it will lead to reduced heart rate, ecstasy, breathing malfunction and finally death.

4. Multi-activation This class of drugs will cause both sedation and hallucination.

Addicted people will be off the right track and deteriorate both physically and mentally. If drug addicts take the drug for a long time, it will destroy their nervous system which causes hallucinations and mental disorders. The drugs in this class are as follow.

Cannabis is an annual crop and grows easily in tropical area. The leaves are digitate

with serrate leaflets. The leaves and flowers contain the drug tetrahydrocannabinol (THC).

Health impacts of marijuana: It will stimulate and depress the central nervous system which leads to muscles shaking, increased heart rate, inability to breathe, confusion, easily changing emotions and hallucination. When used for a long time, it will lead to psychosis.

Withdrawal of marijuana: Patient will be moody, anxious, may get headaches and stomachache and may faint.