A drug is any substance taken into the body that modifies or affects the body’s chemical reactions.

Some drugs are used medicinally to treat various pathogens, their causes, and their symptoms.

The Liver is the organ encharged of breaking down every single drug that enters the body. Therefore an excess of it might result in hepatic diseases.

Most drugs can create addiction or dependence on the user:

• Addiction: The level is mostly genetic, different drugs are addictive in different amounts, and they are addictive mostly due to the quick and effective release of endorphins and dopamine.

• Dependence: Something that is actually organismically needed for survival.

  Drugs can be either depressants or stimulants:

• Stimulants: Blocks the enzyme that breaks down neurotransmitters

  • Keeps the impulse going for longer than it should

  • The neurotransmitters remain in the synaptic cleft.

  • Neurotransmitters constantly bind with the receptors.

• Depressants: Block receptors in the postsynaptic neuron for neurotransmitters, the depressants mimic the neurotransmitters and bind themselves to the receptor.

  • Slows down reactions.

  • Blocks synapses.

Antibiotics

Target bacterial cells affecting their work: damaging cell walls, and blocking proteins needed.

They are effective for bacterial infections, not viral ones because viruses cannot be affected by damaging cell walls since they are not living things.

Antibiotics affect every bacteria in an organism, including benign ones.

Antibiotic resistance

Bacteria, as well as other prokaryotes, reproduce mainly through binary fission a way quicker asexual reproduction type.

As they reproduce so quickly, random mutations coding for resistance to the antibiotic are very likely, and due to natural selection the antibiotic-resistant will survive and reproduce, then the treatment will be useless.

To avoid antibiotic resistance humans should:

• Complete the antibiotic cycles (if it was suggested to take 7 days, then take it ONLY for 7 days)

• Do not use antibiotics for viral infections.

Narcotics or opioids

They work as powerful analgesics (painkillers).

Some of them are severely restricted due to severe withdrawal symptoms. For instance, heroin.

Narcotics are powerful depressants of the Central nervous System.

A particular effect of heroin consumption is the increasement of the HIV rates since more needles are shared due to high costs.

Alcohol

The pathway of alcohol in a human body is:

Ingestion → Digestion → Small intestine → Bloodstream (Portal hepatic vein) → Liver → Central Nervous System.

Short term effects of alcohol consumption

• Reactions are slower

• Lower self-control

• Loss of inhibitions

• Social problems

• Vomiting

• Blocking synaptic receptors

  • Alcohol is a stimulant

Long term effects of alcohol consumption

• Liver damage

• Fwtal Alcohol Syndrome (FAS) → Changes the anatomy of the fetus with ear abnormalities, low nassal, etc.

• Brain damage (HEAVY DRINKING)

• Miscarriage (just linked)

• Domestic violence

Smoking (tobacco)

Contains nicotine, a chemical which is highly addictive:

• Depressant for some neurotransmitters

• Stimulant for some neurotransmitters

• Increased chance of blood clots

  Also contains Tar which is very sticky:

• Destroys cilia in the trachea

• Destroys the alveolli → Produces a disease called Emphysema

• Blocks airways → Due to the cilia damage.

  Additionally, contains Carbon Monoxide, chemical that replaces oxygen in the red blood cells

• Lowers the oxygenation of the blood.

  Links to diseases

  COPD → Obstructive diseases

  Lung cancer

  Coronary heart disease → Blood clots

  During pregnancy:

• Low weight

• Still-birth

• Due to low oxygenation there is the risk of miscarriage.

Performance-enhancing drugs

Types of performance-enhancing drugs:

• Testosterone

• Anabolic steroids → They are a synthetic version of testosterone.