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.

Caffeine: Uses, Mechanism, Dosage, Side Effects & Brands

Explore a complete guide to the drug Caffeine—its introduction, mechanism of action, pharmacokinetics, indications, contraindications, side effects, drug interactions, dosage, brand names, and pricing. Ideal for medical students and 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 & Price  

11. Conclusion

1. Introduction:

Caffeine is a *central nervous system (CNS) stimulant* commonly found in coffee, tea, soft drinks, and energy products. In clinical medicine, *Caffeine Citrate* is used primarily for treating *apnea of prematurity* in neonates and as a stimulant in certain fatigue-related disorders.

2. Mechanism of Action:

Caffeine acts as a *non-selective adenosine receptor antagonist*, which increases neuronal activity and the release of neurotransmitters such as dopamine and norepinephrine. It also *inhibits phosphodiesterase*, increasing cyclic AMP levels, promoting alertness and bronchodilation.

3. Pharmacokinetics and Dynamics:

- *Absorption:* Rapid oral absorption

- *Peak plasma concentration:* 30–60 minutes

- *Half-life:* Adults: 3–7 hours; neonates: up to 100 hours

- *Metabolism:* Liver (CYP1A2)

- *Excretion:* Renal

4. Indications:

- *Apnea of prematurity*

- *Migraine and tension headaches (adjunct)*

- *Fatigue and drowsiness*

- *Post-dural puncture headache*

- *Enhancing alertness and physical performance*

5. Drug of Choice:

- *Apnea of prematurity* – Caffeine citrate is preferred over theophylline due to fewer side effects and simpler dosing.

6. Contraindications:

- Hypersensitivity to caffeine

- Uncontrolled hypertension

- Cardiac arrhythmias

- Severe anxiety disorders

- Peptic ulcer disease (use with caution)

7. Side Effects:

- *Mild:* 

Restlessness, insomnia, tremors, increased urination

- *Moderate:* 

Palpitations, gastrointestinal upset

- *Severe:* 

Arrhythmias, seizures (in high doses), dependency

8. Drug Interactions:

- *Increased effects:* with other stimulants (e.g., ephedrine)

- *Reduced clearance:* with ciprofloxacin, oral contraceptives

- *Reduced effect of:* sedatives like benzodiazepines

- May interact with *CNS-active agents* and increase their side effects

9. Dosage:

- *Apnea of prematurity (Caffeine Citrate):*

  - Loading dose: 20 mg/kg IV/PO

  - Maintenance: 5–10 mg/kg/day

- *Adults (oral tablets):*

  - 100–200 mg every 3–4 hours as needed (max 400 mg/day)

10. Brand Names & Price:

Caffeine Citrate:

  - Brand: Cafcit®️ (USA)  

  - Form: Injection/Oral solution  

  - Price: ~15–50 per vial  

Caffeine Tablets:

  - Brands: NoDoz®️, Vivarin®️, Alert®️  

  - Price: 5–10 per pack of 100 mg tablets

11. Conclusion:

Caffeine is not just a common beverage ingredient but also a *clinically significant drug*. It plays a vital role in neonatal care and fatigue management. While generally safe, its *use must be cautious* in sensitive populations due to potential side effects and drug interactions.