Amphetamine – A Complete Guide to Uses, Dosage, Side Effects & More

Explore the comprehensive medical guide on Amphetamine: its mechanism of action, pharmacokinetics, therapeutic uses, dosage, side effects, contraindications, brand names, price, and antidote. Essential for healthcare professionals and students.

Table of Contents:

1. Introduction  

2. Mechanism of Action  

3. Pharmacokinetics & Pharmacodynamics  

4. Indications  

5. Drug of Choice  

6. Contraindications  

7. Side Effects  

8. Dosage  

9. Brand Names & Price  

10. Antidote  

11. Conclusion

1. Introduction:

Amphetamine is a *central nervous system stimulant* used to treat *ADHD*, *narcolepsy*, and occasionally *obesity*. It enhances alertness, attention, and energy by increasing specific neurotransmitter levels in the brain. It is a *Schedule II controlled substance* due to its high abuse potential.

2. Mechanism of Action:

Amphetamine increases the release of *dopamine* and *norepinephrine* in the brain and inhibits their reuptake. This leads to increased synaptic concentrations, resulting in enhanced focus and alertness.

3. Pharmacokinetics & Pharmacodynamics:

- *Absorption:* Rapid oral absorption  

- *Onset:* 30–60 minutes  

- *Half-life:* 9–14 hours  

- *Metabolism:* Hepatic (CYP2D6 pathway)  

- *Excretion:* Primarily in urine (pH-dependent)

4. Indications:

- Attention-Deficit/Hyperactivity Disorder (ADHD)  

- Narcolepsy  

- Obesity (short-term, off-label)

5. Drug of Choice:

Amphetamine is a *first-line drug* for *ADHD* in children and adults due to its efficacy in improving attention span, behavior, and cognitive function.

6. Contraindications:

- Cardiovascular disease  

- Glaucoma  

- Hyperthyroidism  

- History of substance abuse  

- Use of MAO inhibitors within 14 days  

- Severe agitation or anxiety

7. Side Effects:

Common:

- Insomnia  

- Decreased appetite  

- Dry mouth  

- Restlessness

Serious:

- Hypertension  

- Tachycardia  

- Addiction  

- Psychosis  

- Growth suppression in children

8. Dosage:

ADHD:

- Children: Start at 2.5–5 mg/day, increase as needed  

- Adults: 5–30 mg/day in divided doses

Narcolepsy:

- 5–60 mg/day in divided doses

Note: Dosage should be individualized.

9. Brand Names & Price:

Brand Names:  

- Adderall®️  

- Dexedrine®️  

- Evekeo®️  

- Vyvanse®️ (prodrug: lisdexamfetamine)

Price (US):

- Generic: 20–50/month  

- Branded:100–200/month  

(Prices vary by region and availability)

10. Antidote:

There is *no specific antidote* for amphetamine overdose. *Supportive care* is the mainstay:

- *Activated charcoal* (if early)  

- *Benzodiazepines* for agitation/seizures  

- *Cooling* for hyperthermia  

- *Antihypertensives* if needed  

- Acidifying urine (e.g., ammonium chloride) may enhance excretion

11. Conclusion: 

Amphetamine remains a cornerstone in ADHD and narcolepsy management due to its proven benefits. However, due to its *abuse potential* and possible side effects, medical supervision is essential. Understanding its pharmacology, proper dosing, and safety profile ensures its effective and responsible use.

 

Nicotine: Pharmacology, Medical Use, Side Effects & Dosage

 

Explore the complete pharmacological profile of Nicotine, including its mechanism of action, therapeutic uses, side effects, dosage, contraindications, brand names, price, and more. A must-read for medical students and healthcare professionals.

Table of Contents:

1. Introduction  

2. Mechanism of Action  

3. Pharmacokinetics and Dynamics  

4. Indications  

5. Drug of Choice  

6. Contraindications  

7. Side Effects  

8. Drug Interactions  

9. Dosage  

10. Brand Names and Price  

11. Conclusion

1. Introduction:

Nicotine is a naturally occurring alkaloid found in tobacco plants. It is a *potent stimulant* and highly addictive substance. In medicine, *Nicotine Replacement Therapy (NRT)* is used to help people quit smoking by reducing withdrawal symptoms.

2. Mechanism of Action:

Nicotine binds to *nicotinic acetylcholine receptors (nAChRs)* in the brain and peripheral nervous system, leading to *dopamine release*, which contributes to its addictive potential. It also stimulates the *autonomic ganglia* and adrenal medulla, increasing heart rate and blood pressure.

3. Pharmacokinetics and Dynamics:

- *Absorption:* Rapid via lungs, skin, oral/nasal mucosa  

- *Onset:* Seconds (inhalation), minutes (transdermal)  

- *Metabolism:* Liver (CYP2A6 enzyme)  

- *Half-life:* ~2 hours  

- *Excretion:* Urine

4. Indications:

- *Smoking cessation* (NRT)  

- Management of *nicotine withdrawal symptoms*  

- Investigational use in neurological disorders (e.g., Parkinson’s disease)

5. Drug of Choice:

Nicotine is the *drug of choice in NRT*, especially when tailored through patches, gums, lozenges, nasal sprays, or inhalers to gradually reduce tobacco dependence.

6. Contraindications:

- Recent myocardial infarction  

- Severe cardiac arrhythmias  

- Uncontrolled hypertension  

- Hypersensitivity to nicotine

7. Side Effects:

- *Common:* Headache, nausea, dizziness, mouth/throat irritation  

- *Cardiac:* Tachycardia, palpitations  

- *Skin (patch):* Local irritation, rash  

- *Psychological:* Anxiety, sleep disturbances

8. Drug Interactions:

- *Theophylline*, *warfarin*, and *insulin* levels may be altered  

- *CYP1A2-inducing drugs* can affect nicotine metabolism  

- Smoking induces certain liver enzymes, so stopping may alter metabolism of other drugs

9. Dosage:

- *Transdermal patch:* 7–21 mg/day (based on smoking history)  

- *Gum/lozenge:* 2–4 mg every 1–2 hours (max 24 pieces/day)  

- *Nasal spray:* 1 spray each nostril/hourly  

- Duration: 6–12 weeks, gradually tapering

10. Brand Names and Price:

Brand Names:

  - Nicorette®️ (gum, lozenge)  

  - NicoDerm CQ®️ (patch)  

  - Nicotrol®️ (inhaler, nasal spray)

Prices:

  - Patches: 30–50 for a 2-week pack  

  - Gum/Lozenge:20–40 for 100 pieces

11. Conclusion:

Nicotine, despite its association with tobacco addiction, plays a vital role in *smoking cessation therapy*. When used appropriately in NRT, it significantly increases quit rates and helps reduce the burden of tobacco-related diseases.