1. Merosakkan sistem saraf pusat (otak & saraf tunjang) .
2. Dalam keadaan mabuk atau khayal , penagih tidak dapat mengawal pergerakan dan perimbangan badannya .
3. Risiko jangkitan HIV/AIDS , Hepatatis dan Sawan apabila menggunakan alat suntikan yang dikongsi .
4. Kesan ke atas wanita mengandung iaitu seperti keguguran , kelahiran bayi songsang , lahir belum cukup bulan , kematian bayi semasa lahir /melahirkan bayi yang tidak sempurna/cacat .
5. Melemah dan merosak daya pemikiran , pemahaman , percakapan , pengiraan dan kebolehan menyelesaikan masalah .
6. Menyebabkan gangguan emosi dalam kehidupan keluarga dan masyarakat .
7. Peningkatan kes-kes sosial dan jenayah seperti budaya samseng , kecurian , rompakan , rogol , pembunuhan dan sebagainya . Ini adalah kerana penagih sebenarnya telah mengalami kerosakan otak dan mampu atau sanggup melakukan apa sahaja demi ketagihan mereka kepada dadah .
8. Membawa maut kepada : -
a. Diri sendiri
Contohnya :
Akibatnya daripada pengambilan dos yang berlebihan .
b. Ahli keluarga
Contohnya :
Ibu , kerana tindakan ganas/luar kawalan penagih kerana memerlukan wang untuk membeli dadah .
c. Orang awam
Contohnya :
Kemalangan akibat memandu di bawah pengaruh dadah .
Effects of Substance Abuse
The effects of substance abuse can be felt on many levels: on the individual, on friends and family, and on society.
On the Individual
People who use drugs experience a wide array of physical effects other than those expected. The excitement of a cocaine high, for instance, is followed by a “crash”: a period of anxiety, fatigue, depression, and an acute desire for more cocaine to alleviate the feelings of the crash. Marijuana and alcohol interfere with motor control and are factors in many automobile accidents. Users of marijuana and hallucinogenic drugs may experience flashbacks, unwanted recurrences of the drug's effects weeks or months after use. Sudden abstinence from certain drugs results in withdrawal symptoms. For example, heroin withdrawal can cause vomiting, muscle cramps, convulsions, and delirium. With the continued use of a physically addictive drug, tolerance develops; i.e., constantly increasing amounts of the drug are needed to duplicate the initial effect. Sharing hypodermic needles used to inject some drugs dramatically increases the risk of contracting AIDS and some types of hepatitis. In addition, increased sexual activity among drug users, both in prostitution and from the disinhibiting effect of some drugs, also puts them at a higher risk of AIDS and other sexually transmitted diseases. Because the purity and dosage of illegal drugs are uncontrolled, drug overdose is a constant risk. There are over 10,000 deaths directly attributable to drug use in the United States every year; the substances most frequently involved are cocaine, heroin, and morphine, often combined with alcohol or other drugs. Many drug users engage in criminal activity, such as burglary and prostitution, to raise the money to buy drugs, and some drugs, especially alcohol, are associated with violent behavior.
Effects on the Family
The user's preoccupation with the substance, plus its effects on mood and performance, can lead to marital problems and poor work performance or dismissal. Drug use can disrupt family life and create destructive patterns of codependency, that is, the spouse or whole family, out of love or fear of consequences, inadvertently enables the user to continue using drugs by covering up, supplying money, or denying there is a problem. Pregnant drug users, because of the drugs themselves or poor self-care in general, bear a much higher rate of low birth-weight babies than the average. Many drugs (e.g., crack and heroin) cross the placental barrier, resulting in addicted babies who go through withdrawal soon after birth, and fetal alcohol syndrome can affect children of mothers who consume alcohol during pregnancy. Pregnant women who acquire the AIDS virus through intravenous drug use pass the virus to their infant.
Effects on Society
Drug abuse affects society in many ways. In the workplace it is costly in terms of lost work time and inefficiency. Drug users are more likely than nonusers to have occupational accidents, endangering themselves and those around them. Over half of the highway deaths in the United States involve alcohol. Drug-related crime can disrupt neighborhoods due to violence among drug dealers, threats to residents, and the crimes of the addicts themselves. In some neighborhoods, younger children are recruited as lookouts and helpers because of the lighter sentences given to juvenile offenders, and guns have become commonplace among children and adolescents. The great majority of homeless people have either a drug or alcohol problem or a mental illness—many have all three.
The federal government budgeted $17.9 billion on drug control in 1999 for interdiction, prosecution, international law enforcement, prisons, treatment, prevention, and related items. In 1998, drug-related health care costs in the United States came to more than $9.9 billion.
毒品的危害
一、吸毒对身心的危害
(1) 吸毒对身体的毒性作用: 毒性作用是指用药剂量过大或用药时间过长引起的对身体的一种有害作用，通常伴有机体的功能失调和组织病理变化。
中毒主要特征有：嗜睡、感觉迟钝、运动失调、幻觉、妄想、定向障碍等
(2) 戒断反应：是长期吸毒造成的一种严重和具有潜在致命危险的身心损害，通常在突然终止用药或减少用药剂量后发生。许多吸毒者在没有经济来源购毒、吸毒的情况下，或死于严重的身体戒断反应引起的各种并发症，或由于痛苦难忍而自杀身亡。戒断反应也是吸毒者戒断难的重要原因。
(3) 精神障碍与变态：吸毒所致最突出的精神障碍是幻觉和思维障碍。他们的行为特点围绕毒品转，甚至为吸毒而丧失人性。
(4)感染性疾病：静脉注射毒品给滥用者带来感染性合并症，最常见的有化脓性感染和乙形肝炎，及令人担忧 的艾滋病问题。此外，还损害神经系统、免疫系统，易感染各种疾病。
二、吸毒对社会的危害。
(1)对家庭的危害：家庭中一旦出现了吸毒者,家便不成其为家了。吸毒者在自我毁灭的同时，也破害自己的家庭，使家庭陷入经济破产、亲属离散、甚至家破人亡的困难境地。
(2) 对社会生产力的巨大破坏: 吸毒首先导致身体疾病，影响生产，其次是造成社会财富的巨大损失和浪费, 同时毒品活动还造成环境恶化, 缩小了人类的生存空间。
(3) 毒品活动扰乱社会治安: 毒品活动加剧诱发了各种违法犯罪活动，扰乱了社会治安, 给社会安定带来巨大威胁。
无论用什么方式吸毒，对人体的肌体都会造成极大的损害。
一、静脉注射毒品
（1）静脉注射阿片类毒品的危害最大，后果严重而且是多方面的：不洁注射导致感染各种疾病，如细菌性心内膜炎，破伤风、败血病、横断性脊髓炎，并极易传染乙肝、丙肝等血清型肝炎。不洁注射是传播艾滋病毒的重要途径。
（2）注射阿片类毒品对人体的免疫功能有着直接和全面的损害。静脉注射毒品，最容易引发吸毒过量死亡，国内外大量的统计已经充分证明了这一点。
二、肌肉或皮下注射毒品
注射部位的皮肤可能出现脓肿、感染、色素沉着、疤痕硬结等症状。
三、通过呼吸道途径吸食毒品
是指毒品加温后通过呼吸道进入人体的吸食方式。长期吸食对呼吸道系统造成恶性刺激，轻者易患气管炎，重者导致肺炎、肺气肿和肺癌。
