PreReg solution

17/08/2025

**Calcium-Channel Blockers (CCBs) – Quick Guide**

# # # **Types of CCBs**
1. **Dihydropyridines** (Amlodipine, Felodipine, Nifedipine) – Best for **hypertension**.
- Avoid in **uncontrolled heart failure** (except amlodipine).
- **Amlodipine** is often preferred (cost-effective).

2. **Rate-Limiting CCBs** (Verapamil, Diltiazem) – Used for **angina** if beta-blockers aren’t suitable.
- Avoid in **heart failure, AV block, or bradycardia**.

# # # **Key Points**
✔ **Avoid in heart failure** (except amlodipine in stable cases).
✔ **Once-daily dosing** preferred (amlodipine, modified-release verapamil/diltiazem).
✔ **Start low, titrate up** every 4 weeks based on BP response.

# # # **Contraindications**
❌ **Heart failure** (especially verapamil/diltiazem).
❌ **Severe aortic stenosis, cardiogenic shock**.
❌ **AV block** (verapamil/diltiazem contraindicated in 2nd/3rd degree).

# # # **Common Side Effects**
- Swelling (ankles), headache, dizziness, flushing.
- **Verapamil/Diltiazem**: Bradycardia, constipation.

# # # **Drug Interactions**
⚠ **Beta-blockers + Verapamil/Diltiazem** → Risk of severe bradycardia.
⚠ **Grapefruit juice** ↑ CCB levels → Avoid!
⚠ **Digoxin, statins, DOACs** may need dose adjustments.

# # # **Dosing**
- **Amlodipine**: Start 5 mg daily (max 10 mg).
- **Verapamil MR**: Start 120–240 mg daily.
- **Diltiazem MR**: Brand-specific dosing.

**CCBs are versatile but choose based on comorbidities!**

07/08/2025

Doxycycline Cheat Sheet 📝

💊 What is it?
Antibiotic (tetracycline class) used for infections & malaria prevention.

🦠 Common Uses:
✔️ Malaria prophylaxis
✔️ Acne, Lyme disease, chlamydia
✔️ Bacterial infections (sinusitis, pneumonia)

⚠️ Key Warnings:
🚫 Avoid in:

Pregnancy (harms baby’s teeth/bones)

Kids

29/07/2025

27/07/2025

💊 NSAIDs: What You Need to Know

🔹 GI Risks All NSAIDs can cause ulcers & bleeding. Highest risk Piroxicam, ketoprofen, ketorolac. Lowest risk Low-dose ibuprofen. COX-2 inhibitors (e.g., celecoxib)have **less GI toxicity than traditional NSAIDs.

🔹 Heart Risks
- **↑ Thrombosis risk( MI/stroke) with COX-2 inhibitors, diclofenac (150mg/day), high-dose ibuprofen (2.4g/day)
- Naproxen (1g/day) = safer for heart
- Low-dose ibuprofen (≤1.2g/day) = minimal CV risk.

🔹 Key Rules
✔ Lowest dose, shortest time possible.
✔ Avoid in active ulcers(if needed, add PPI).
✔ Never combine oral NSAIDs(↑ toxicity).
✔ Caution with aspirin(↑ bleeding risk).

⚠ Elderly & high-risk? Use naproxen (CV-safe) + PPIor COX-2 + PPI if GI concerns.

**💊 NSAIDs: What You Need to Know**

🔹 **GI Risks**: All NSAIDs can cause ulcers & bleeding. **Highest risk**: Piroxicam, ketoprofen, ketorolac. **Lowest risk**: Low-dose ibuprofen. **COX-2 inhibitors (e.g., celecoxib)** have **less GI toxicity** than traditional NSAIDs.

🔹 **Heart Risks**:
- **↑ Thrombosis risk** (MI/stroke) with **COX-2 inhibitors, diclofenac (150mg/day), high-dose ibuprofen (2.4g/day)**.
- **Naproxen (1g/day) = safer for heart**.
- Low-dose ibuprofen (≤1.2g/day) = minimal CV risk.

🔹 **Key Rules**:
✔ **Lowest dose, shortest time** possible.
✔ **Avoid in active ulcers** (if needed, add PPI).
✔ **Never combine oral NSAIDs** (↑ toxicity).
✔ **Caution with aspirin** (↑ bleeding risk).

⚠ Elderly & high-risk? Use naproxen (CV-safe) + PPIor COX-2 + PPI if GI concerns.

💊

27/07/2025

**💊 NSAIDs: What You Need to Know**

🔹 **GI Risks**: All NSAIDs can cause ulcers & bleeding. **Highest risk**: Piroxicam, ketoprofen, ketorolac. **Lowest risk**: Low-dose ibuprofen. **COX-2 inhibitors (e.g., celecoxib)** have **less GI toxicity** than traditional NSAIDs.

🔹 **Heart Risks**:
- **↑ Thrombosis risk** (MI/stroke) with **COX-2 inhibitors, diclofenac (150mg/day), high-dose ibuprofen (2.4g/day)**.
- **Naproxen (1g/day) = safer for heart**.
- Low-dose ibuprofen (≤1.2g/day) = minimal CV risk.

🔹 **Key Rules**:
✔ **Lowest dose, shortest time** possible.
✔ **Avoid in active ulcers** (if needed, add PPI).
✔ **Never combine oral NSAIDs** (↑ toxicity).
✔ **Caution with aspirin** (↑ bleeding risk).

⚠ Elderly & high-risk? Use naproxen (CV-safe) + PPIor COX-2 + PPI if GI concerns.

💊

26/07/2025

Definition:
Heart failure is a long-term condition where the heart struggles to pump enough blood due to structural or functional weakness.  

🔍 How to Spot It
• Symptoms: Breathlessness (especially with activity or lying flat), swelling in legs/ankles, fatigue, weight gain, dry cough 
• Signs: Raised JVP, crackles in lungs, peripheral edema, cardiomegaly, abnormal ECG 

➡️ Tests: NT‑proBNP levels, ECG, chest X‑ray, echocardiogram, and relevant bloods 

⸻

💊 Treatment Pathway for HFrEF (EF ≤ 40%)
1. First line: ACE inhibitors + beta‑blockers
2. Add: Mineralocorticoid receptor antagonist if symptoms persist
3. Specialists may initiate:
• Sacubitril‑valsartan
• SGLT2 inhibitors: Dapagliflozin & Empagliflozin added to optimized therapy

25/07/2025

Deficiency in vitamin B12 or folate leads to megaloblastic anaemia. This condition is characterized by abnormally large red blood cells (macrocytosis) with a mean cell volume (MCV) greater than 100 fL, caused by impaired DNA synthesis.

2. COMMON CAUSES

Vitamin B12 Deficiency:

Pernicious Anaemia: The most common cause of severe B12 deficiency in the UK.

Dietary: Vegan or malnourished diets.

Gastric Issues: Gastrectomy, Zollinger-Ellison syndrome.

Medications: Metformin, protein pump inhibitors (PPIs), H2-receptor antagonists.

Intestinal Issues: Crohn’s disease, ileal resection, malabsorption.

Folate Deficiency:

Dietary: Poor intake is a primary cause. Good sources include broccoli, chickpeas, and brown rice.

Increased Requirements: Pregnancy, malignancy.

Medications: Alcohol, methotrexate, trimethoprim, anticonvulsants.

Other: Liver disease, malabsorption (e.g., Coeliac disease).

22/07/2025

Emergency contraception.

💊

20/07/2025

20/07/2025

SSRI ( selective serotonin reuptake inhibitors)- this includes
Fluoxetine - considered safe in children
Sertraline - considered safe in MI patients
Paroxetine- risk of withdrawal
Citalopram- risk of QT interval prolongation.

All SSRIs → Risk of bleeding, hyponatremia, serotonin syndrome

19/07/2025

💊 How PPIs Work:
PPIs block the gastric H+/K+ ATPase enzyme (proton pump) in stomach lining cells. This reduces stomach acid production

19/07/2025

Proton Pump Inhibitors (PPIs) – Mechanism of Action

💊 How PPIs Work:
PPIs block the gastric H+/K+ ATPase enzyme (proton pump) in stomach lining cells. This reduces stomach acid production

PPI Examples:

Omeprazole

Esomeprazole

Lansoprazole

Pantoprazole

Rabeprazole

💊