Why Drugs are Prohibited in Islam

The objectives of Islam include preserving the religion and the human soul, honor, mind and wealth. Any substance or act that harms any of these five matters is considered unlawful in Islam.

The enemies of Islam and humanity have fought against this religion, and have attempted to distance Muslims from their religion using different means. Allaah The Almighty Says (what means):
{They ask you concerning fighting in the Sacred Months (i.e. 1st, 7th, 11th and 12th months of the Islaamic calendar). Say, `Fighting therein is a great (transgression) but a greater (transgression) with Allaah is to prevent mankind from following the way of Allaah, to disbelieve in Him, to prevent access to Al-Masjid Al-Haraam (at Makkah), and to drive out its inhabitants, and Al-Fitnah is worse than killing.' And they will never cease fighting you until they turn you back from your religion (Islaamic Monotheism) if they can. And whosoever of you turns back from his religion and dies as a disbeliever – for those, their deeds have become worthless in this world and the Hereafter....
[Qur`an 2: 217].

The enemies of Islam and humanity fully recognise the fact that the sole source of the Muslims' strength lies in their commitment to Islam. Thus, they use the most evil and lowly means in order to control and corrupt the Muslim nation. They realize that the quickest means to destroy the Muslim youth is by using the weapon of desires: seductive women, alcohol and drugs.
The worst, and most effective, of these has beenthe weapon of drugs, because it is directed at the heart of the Muslim nation and its protective shield, the youth who shoulder the responsibility of protecting the Muslim nation and advancing it on the path to progress. When the youth are destroyed, the entire nation heads to destruction, and it becomes easy pickings for anyone to eat from and devour its resources and wealth
Islam prohibits the use of all types of intoxicants, whether in the form of a drink, pills, drops, inhaled substances, needles, etc. The evidences for the prohibition are as follows:
· Allaah The Almighty Says (what means):
{Those who follow the Messenger, the Prophet who can neither read nor write (i.e. Muhammad) whom they find written with them in the Tawraat (Torah) (Deut, xviii 15) and the Injeel (Gospel) (John, xiv 16), 
ـ he commands them for Al-Ma`roof (i.e. Islamic Monotheism and all that Islam has ordained); and forbids them from Al-Munkar (i.e. disbelief, polytheism of all kinds, and all that Islam has forbidden); he allows them as lawful At-Tayyibaat (i.e. all good and lawful as regards things, deeds, beliefs, persons and foods), and prohibits them as unlawful Al-Khabaa'ith (i.e. all evil and unlawful as regards things, deeds, beliefs, persons and foods), he releases them from their heavy burdens (of Allaah's Covenant with the Children of Israel), and from the fetters (bindings) that were upon them. So those who believe in him (Muhammad), honour him, help him, and follow the light (the Quran) which has been sent down with him, it is they who will be successful.}                                 
[Quran 7: 157]
and there is no doubt that drugs come under the definition of Khabaa’ith.
· Allaah The Almighty Says (what means):
{O you who believe! Eat not up your property among yourselves unjustly except it be a trade amongst you, by mutual consent. And do not kill yourselves (nor kill one another). Surely, Allaah is Most Merciful to you.}[Quran 4: 29]. It has been proven scientifically that consuming drugs eventually leads to death.
·  Umm Salamah may  Allaah  be  pleased  with  her narrated, “The Prophet  sallallaahu  `alayhi  wa  sallam ( may  Allaah exalt his mention ) prohibited anything which makes a person drunk or feeble (or causes numbness to the brain).”[Ahmad].
Muslim scholars over centuries have also condemned the use of intoxicating and hallucinogenic substances.
·              Ibn Taymiyyah,  may  Allaah  have  mercy  upon  him said, "Hashish is prohibited whether it causes a person to lose control over his mind or not; it is worthier in being prohibited than alcohol because its harm is more than that of alcohol."
·              Shaykh Muhammad Aal Ash-Shaykh, may  Allaah  have  mercy  upon  him said, "Ibn Hajar conveyed the statements of all four Imaams of jurisprudence who prohibited drugs."
·              Shaykh Jaad Al-Haqq, the grand Mufti of Egypt, said on 4/5/1399 A.H., "It is the consensus of all Muslim scholars that producing all types of drugs, planting them, trading in them or using them is prohibited, and that the one who does any of that should be punished."