What is Amphetamine?
Amphetamine is a central nervous system (CNS) stimulator used to treat medical conditions like Attention Deficit Hyperactivity Disorder (ADHD) and narcolepsy.
CNS stimulators affect the chemicals in the brain and cause hyperactivity and impulse control.
ADHD is a complex psychological disorder caused by genetic and non-genetic factors.
It is the most common neurodevelopmental disorder occurring in childhood.
Children with ADHD have trouble paying attention, controlling impulsive behaviors, and being overly active.
Aside from its medical uses, Amphetamine is also a habit-forming (highly addictive) substance with a long history of abuse.
Apart from a few brands, Amphetamine is not recommended for children below the age of three years.
Today, Amphetamine is also being used for treating obesity, depression, and chronic pain, although off-label.
How Does Amphetamine Work?
Amphetamine is a CNS stimulant that increases the amount of neurotransmitters (chemical messengers) like dopamine, norepinephrine, and serotonin in the synapse via different mechanisms.
A synapse is a small gap between two nerve cells where transmission of electrical impulses occurs.
Amphetamine enters the nerve cell at the synapse by diffusion and is taken up by transporter molecules at the synapse.
Once inside the nerve cell, Amphetamine disrupts the electrochemical gradients required for standard impulse transmission.
Amphetamine also inhibits the metabolism of monoamine neurotransmitters (chemical modifications that monoamine transmitters undergo) by inhibiting Monoamine Oxidase (MAO) enzymes.
MAO inhibitors are responsible for degrading neurotransmitters. So, if Amphetamine inhibits MAO, the quantity of specific neurotransmitters increases.
What Are The Side Effects Of Amphetamine?
Though Amphetamine is safe when taken legally and in doses strictly prescribed by the doctor, some people may experience mild to severe side effects on taking it.
These side effects may be physical or psychological.
Physical side effects of Amphetamine include:
- Increased or decreased blood pressure
- Reduced blood flow to the hands and legs (Raynaud’s Phenomenon)
- Erectile dysfunction
- Increased or rapid heart rate
- Abdominal pain
- Nausea
- Appetite loss
- Weight loss
- Acne, hives, and skin rash
- Blurred vision
- Nose bleeding
- Nasal congestion
- Profuse sweating
- Dry mouth
- Teeth grinding
- Increased risk of seizures
- Difficulty in passing urine
Psychological side effects of taking Amphetamine may include:
- Mood swings
- Changes in libido
- Apprehension
- Anxiety
- Irritability
- Restlessness
- Increased alertness and focus
- Obsessive behavior
- An exaggerated sense of one’s importance
- Psychosis (may occur in rare cases)
Some studies have also shown that when Amphetamine is used to treat ADHD in children, it can retard or slow down growth.
Some minor effects have also been observed in the cardiovascular system, including increased heart rate and blood pressure.
However, more research is required to confirm this.
When Amphetamine is taken at higher doses or through routes not prescribed by a doctor, the risk of adverse effects increases.
Taking excess Amphetamine increases dopamine levels in the brain.
Overuse or abuse of Amphetamine may lead to:
- Delusions
- Feeling of paranoia
- Cardiovascular problems, including stroke
- Reduced capability of reasoning, problem-solving, etc.
- Breakdown of muscles (muscle wastage)
- Malnutrition (reduced nutrient intake or poor nutrition)
People who take Amphetamine for recreational purposes may also experience withdrawal symptoms like depression and sleep disturbances when they stop taking the drug.
Interactions Of Amphetamine With Other Drugs
Many drugs, nutritional supplements, and herbal supplements may interact with Amphetamine.
Therefore, you must always inform your doctor about medications or supplements you are currently taking.
Drug interactions may change how drugs work and increase the risk of adverse reactions.
Some drugs that interaction with Amphetamine are:
- MAO inhibitors
Monoamine Oxidase Inhibitors of MAO inhibitors are a class of drugs used to treat depression.
Taking MAO inhibitors with Amphetamine may cause serious and possibly fatal drug interactions.
Therefore, you must avoid taking Amphetamine with MAO inhibitors like isocarboxazid, linezolid, metaxalone, methylene blue, etc.
You must also avoid taking MAO inhibitors for two weeks before taking Amphetamine.
Speak to your doctor to know when you should stop taking MAO inhibitors before starting on Amphetamine.
- Drugs that increase serotonin production
If you are taking drugs like methadone, dextromethorphan, or methylenedioxymethamphetamine (also called ecstasy) that increase serotonin production, taking Amphetamine can lead to serotonin syndrome or toxicity.
- Dextroamphetamine or lisdexamfetamine
Amphetamine is similar to dextroamphetamine or lisdexamfetamine.
To avoid adverse effects or overdose, you must not take these medications together.
Amphetamine may interfere with routine lab tests like blood, urine analysis, and brain scan for Parkinson’s disease and give false results.
So, you must inform your doctor if you are taking Amphetamine before undergoing these tests.
Gene-Drug Interactions: Amphetamine
CYP2D6 Gene
The CYP2D6 gene gives instructions for the production of Cytochrome P450 Family 2 Subfamily D Member 6 enzyme.
The CYP2D6 enzyme plays a vital role in the metabolism of most psychostimulants (drugs that can stimulate the central nervous system), including Amphetamines.
Over 100 forms of the CYP2D6 gene have been identified.
They are classified as normal function, decreased function, or no function.
Though most people carry two copies of the CYP2D6, a few people might have more than two copies.
Individuals who carry one decreased function allele and one no function allele of the CYP2D6 are called intermediate metabolizers of Amphetamine.
Individuals who have two no-function alleles of the gene are called poor metabolizers of the drug.
A majority of people carry two normal function alleles of the CYP2D6 and are normal metabolizers of Amphetamine.
DRD2 Gene
The DRD2 gene gives instructions for producing the Dopamine Receptor D2 subtype.
A particular mutation or abnormal change in this gene may cause myoclonus dystonia whereas other mutations may cause schizophrenia.
The DRD2 is also called the ‘pleasure-seeking gene due to its association with addictions.
People with the A1 type of the DRD2 gene are more prone to addictions of various kinds, including Amphetamine drug addiciton.
Recommendations For The Safe Use Of Amphetamine
- Medical history
Some medical conditions can make it unsafe to take Amphetamine. Inform your doctor about any medical conditions that you may have, particularly:
- Cardiovascular diseases
- Moderate to severe hypertension (high blood pressure)
- History of depression, bipolar disorder, Tourette’s syndrome
- Glaucoma
- Suicidal tendency
- Hyperthyroidism (overactive thyroid)
- Children and teenagers who have a heart problem
- Sensitivity to the drug
If you have a history of sensitivity or allergy to Amphetamine, you must avoid taking the drug.
- History of addictions and drug abuse
If you have a history of drug abuse or addictions, you must not take Amphetamine and inform your doctor about the same.
- Pregnancy and breastfeeding
Inform your doctor if you are pregnant or are planning a pregnancy. Taking Amphetamine during pregnancy may cause premature birth, low birth weight of the baby, or withdrawal symptoms in the newborn.
Since Amphetamine can pass into breast milk and harm your baby, you must inform your doctor if you are breastfeeding before taking the drug.
- Genetic testing
Genetic testing helps your doctor understand how a particular drug may affect you. It can also help them determine the appropriate dosage for you based on your medical history, medications you are taking, and history of addictions.
Before taking Amphetamine, genetic testing for the CYP2D6 and DRD2 genes may be helpful to determine how you will metabolize the drug without causing side effects.
Analyze Your Genetic Response to Amphetamine
Summary
- Amphetamine is a central nervous system (CNS) stimulator used to treat ADHD and narcolepsy.
- Apart from being used legally for treating medical conditions, Amphetamine is also a habit-forming substance.
- Amphetamine works by increasing the level of neurotransmitters like dopamine, norepinephrine, and serotonin in the brain.
- Amphetamine is known to inhibit monoamine oxidase enzymes.
- Though largely safe when prescribed by a doctor, Amphetamine can cause physical and psychological side effects.
- People who take Amphetamine for recreational purposes may also experience withdrawal symptoms when they stop taking the drug suddenly.
- Amphetamine may interact with some drugs and nutritional and herbal supplements.
- Two significant genes that affect the metabolism of Amphetamine are the CYP2D6 and DRD2 genes.
- To ensure safe consumption of Amphetamine, you must inform your doctor about your medical history, current medications, your pregnancy and lactation status.
- Genetic testing for CYP2D6 and DRD2 genes can help your doctor understand your response to Amphetamine and possible side effects.
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