“Beta-blockers for everyone?”
Well, not quite. Sometimes prescribing them is like handing a sleepy man a sedative — it might look logical until he stops breathing.
During our CCU rounds last week, a 68-year-old gentleman from Tump (Kech district) came in with a slow AF and a BP of 90/60. His nephew had already googled “best medicine for heart rate control” and was asking for propranolol like it was Panadol. 😑
Of course, if you’ve practiced with the likes of Dr. Imran Baloch (Cardiology whisperer) or been grilled by Dr. Basit Khan, you’ll know beta-blockers are great — but not always safe.
🔑 Mnemonic: “ABCDE” — Contraindications to Beta-Blockers
| Letter | Condition | Explanation |
|---|---|---|
| A | Asthma | Non-selective beta-blockers can trigger bronchospasm — wheeze city 🚑 |
| B | Heart Block | Especially 2nd or 3rd degree — may worsen bradycardia or complete the block 🧱 |
| C | COPD (severe) | Non-selective ones can worsen airflow limitation — especially in brittle lungs 😮💨 |
| D | Diabetes Mellitus | Can mask hypoglycemia symptoms like tachycardia — diabetic ninja attacks 🥷🍬 |
| E | Electrolyte imbalance | Especially hyperkalemia — worsens AV nodal suppression, arrhythmia risk ⚡ |
Why knowing beta-blocker contraindications matter?
A few months ago, a retired school principal from Zhob was admitted with bradycardia (HR 42), known COPD, and uncontrolled diabetes. Junior staff had charted carvedilol for borderline hypertension.
The next morning — confusion, low BP, wheezing, and blood sugar of 38. 🤦♂️
Cue Dr. Bilal Chaudhary whispering, “Classic beta-blocker train wreck.”
We reversed the bradycardia with atropine, corrected the glucose, called off the beta-blocker, and gave salbutamol. Lesson learned: always screen the ABCDEs before reaching for that metoprolol.
💡 Key Clinical Pearls
- Use cardioselective beta-blockers (e.g., bisoprolol) in COPD or asthma only if absolutely necessary — and never in acute exacerbations.
- Always check ECG for heart block before starting — especially in elderly patients or those on other nodal blockers (like diltiazem).
- Monitor blood glucose in diabetic patients on beta-blockers — hypoglycemia without warning signs is not a fun surprise.
- Don’t forget the serum K+ — especially in CKD or those on ACE inhibitors/spironolactone. Hyperkalemia + AV nodal suppression = 🎯 for asystole.
- Be cautious when treating patients from rural areas (like Mashkai or Nokundi) who may have limited follow-up. The safest drug is the one they won’t need emergency resuscitation from.
Authored by:
Dr. Aurangzaib Qambrani
MBBS | PLAB | MRCP (UK)
Sheikh Khalifa Bin Zayed Hospital, Quetta
