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Cocaine (Coke/Crack): Coca Plant and Its Effect on the Nervous System

Biology · Human Health and Diseases · NEET

Cocaine (also called coke or crack) is a coca alkaloid obtained from the plant Erythroxylum coca, native to South America. It interferes with the transport of the neurotransmitter dopamine, giving a strong stimulating action on the central nervous system with a sense of euphoria and increased energy. Memory hook: "Coke = Coca = CNS stimulant that traps Dopamine" (all start with C).
Cocaine: Source and Effect on the Nervous SystemCoca plantErythroxylum coca(South America)Cocaine"coke" / "crack", snortedBlocks DOPAMINEtransport in CNSCNS stimulanteuphoria, more energyExcess dose to remember:High dose of cocaine causes HALLUCINATIONS (like Atropa belladonna, Datura)
Cocaine is a coca alkaloid from Erythroxylum coca; it blocks dopamine transport and stimulates the CNS (euphoria, energy), while excess dose causes hallucinations.

Your doubts, answered

Which plant is cocaine obtained from?

Cocaine (coca alkaloid) is obtained from the coca plant Erythroxylum coca, which is native to South America. Do not confuse it with Papaver somniferum (opium poppy, source of morphine and heroin) or with Cannabis sativa (marijuana). For NEET, remember the exact name Erythroxylum coca, because the source plant is a very common one-line question.

Is cocaine a stimulant or a depressant?

Cocaine is a STIMULANT. It has a potent stimulating action on the central nervous system (CNS), producing a sense of euphoria and increased energy. This is the opposite of heroin, which is a depressant that slows down body functions. NEET often tests this stimulant-vs-depressant difference, so keep cocaine = stimulant and heroin = depressant clear in your mind.

Which neurotransmitter does cocaine affect?

Cocaine interferes with the transport of the neurotransmitter DOPAMINE. It blocks dopamine from being taken back, so dopamine stays longer, causing the euphoria and increased energy. In NEET match-the-column questions, the correct pairing is always Cocaine with 'interferes with transport of dopamine'.

What is the difference between crack and smack?

Crack is a form of COCAINE (coca alkaloid, a stimulant from Erythroxylum coca). Smack is HEROIN, which is chemically diacetylmorphine (a depressant from the opium poppy). NEET has directly tested this: 'Diacetylmorphine is also called smack.' So crack = cocaine, smack = heroin. Do not mix them up.

What happens in excessive dosage of cocaine?

According to NCERT, excessive dosage of cocaine causes hallucinations. Other well-known plants with hallucinogenic properties are Atropa belladonna and Datura. Remember: normal cocaine effect = euphoria and increased energy (stimulant); excess dose = hallucinations.

⚠️ The NEET trap
✗ Cocaine is obtained from Papaver somniferum.
✓ Cocaine is obtained from Erythroxylum coca. Papaver somniferum is the opium poppy, the source of morphine and heroin, not cocaine.
🧠 Papaver = Poppy = Painkiller (morphine). Coca = Coke = Cocaine. Match the first letters and you will never swap the source plants.

Real NEET questions

NEET 2019 (Odisha)

Coca alkaloid or cocaine is obtained from:

A · Papaver somniferum
B · Atropa belladonna
C · Erythroxylum coca ✓
D · Datura
Solution: Coca alkaloid or cocaine is obtained from the coca plant Erythroxylum coca, native to South America. Papaver somniferum is the opium poppy (morphine/heroin); Atropa belladonna and Datura are hallucinogenic plants, not the source of cocaine.
NEET 2023 (Phase 1)

Match List I with List II: A. Heroin B. Marijuana C. Cocaine D. Morphine I. Effect on cardiovascular system II. Slow down body function III. Painkiller IV. Interfere with transport of dopamine

A · A-II, B-I, C-IV, D-III ✓
B · A-I, B-II, C-III, D-IV
C · A-IV, B-III, C-II, D-I
D · A-III, B-IV, C-I, D-II
Solution: Heroin is a depressant that slows body functions (A-II). Marijuana (cannabinoids) affects the cardiovascular system (B-I). Cocaine interferes with transport of dopamine (C-IV). Morphine is a sedative and painkiller (D-III). Only option A links every drug correctly.
NEET 2023 (Phase 2)

Diacetyl morphine is also called as:

A · Crack
B · Smack ✓
C · Amphetamine
D · Barbiturate
Solution: Heroin is chemically diacetylmorphine, obtained by acetylation of morphine, and is commonly called smack. Crack is a form of cocaine; amphetamine and barbiturate are separate drugs. This shows the crack-vs-smack trap: crack = cocaine, smack = heroin.

Solved Human Health and Diseases NEET PYQs

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Frequently asked

Is cocaine natural or synthetic?

Cocaine is a natural coca alkaloid extracted from the coca plant Erythroxylum coca. It is not a synthetic drug like amphetamines or barbiturates.

Where is the coca plant native to?

The coca plant Erythroxylum coca is native to South America. This region detail is sometimes added in NEET explanations.

How is cocaine usually taken?

According to NCERT, cocaine (commonly called coke or crack) is usually snorted (taken through the nose).

Which drugs are the common coca alkaloid, opioid and cannabinoid examples for NEET?

Coca alkaloid = cocaine (from Erythroxylum coca). Opioids = morphine and heroin (from Papaver somniferum). Cannabinoids = marijuana and hashish (from Cannabis sativa). Grouping them this way helps you answer match-the-column questions quickly.

Related concepts:
Opioids: Morphine, Heroin (Smack) and the Poppy PlantCannabinoids: Marijuana, Hashish and Cannabis sativaTobacco and Nicotine: Effects on the Heart and LungsDrugs and Alcohol Abuse: What Abuse and Addiction MeanAddiction, Dependence and Withdrawal Syndrome
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