You do not need to memorise every drug. Gulf exams test whether you can recognise a drug's class from its name, know the one or two checks before you give it, and know the antidote when things go wrong.
Recognise the class from the name
-olol
Class
Beta blocker
Example
metoprolol, atenolol
Check before giving / watch for
Hold and report if pulse below 60 or low BP; can hide signs of hypoglycaemia; caution in asthma
-pril
Class
ACE inhibitor
Example
enalapril, lisinopril
Check before giving / watch for
First-dose low BP, dry cough, high potassium; angioedema (swollen lips/tongue) is an emergency
-sartan
Class
ARB
Example
losartan, valsartan
Check before giving / watch for
Low BP, high potassium; no cough
-dipine
Class
Calcium channel blocker
Example
amlodipine, nifedipine
Check before giving / watch for
Low BP, headache, flushing, ankle swelling
-statin
Class
Statin
Example
atorvastatin, simvastatin
Check before giving / watch for
Report unexplained muscle pain or weakness
-prazole
Class
Proton pump inhibitor
Example
omeprazole, pantoprazole
Check before giving / watch for
Give before breakfast
-tidine
Class
H2 blocker
Example
famotidine
Check before giving / watch for
Reduces stomach acid
-azepam, -zolam
Class
Benzodiazepine
Example
diazepam, midazolam
Check before giving / watch for
Sedation, slow breathing; fall risk
-cillin
Class
Penicillin
Example
amoxicillin
Check before giving / watch for
Ask about penicillin allergy first
-mycin, -micin
Class
Aminoglycoside (gentamicin)
Example
gentamicin, amikacin
Check before giving / watch for
Kidney damage and hearing loss; drug levels
-floxacin
Class
Fluoroquinolone
Example
ciprofloxacin
Check before giving / watch for
Tendon pain or rupture; separate from antacids
-parin
Class
Heparin
Example
enoxaparin
Check before giving / watch for
Bleeding (see Lesson 11)
-sone, -olone
Class
Corticosteroid
Example
prednisolone, hydrocortisone
Check before giving / watch for
High glucose, infection risk; do not stop suddenly after long use
| Ending | Class | Example | Check before giving / watch for |
|---|---|---|---|
| -olol | Beta blocker | metoprolol, atenolol | Hold and report if pulse below 60 or low BP; can hide signs of hypoglycaemia; caution in asthma |
| -pril | ACE inhibitor | enalapril, lisinopril | First-dose low BP, dry cough, high potassium; angioedema (swollen lips/tongue) is an emergency |
| -sartan | ARB | losartan, valsartan | Low BP, high potassium; no cough |
| -dipine | Calcium channel blocker | amlodipine, nifedipine | Low BP, headache, flushing, ankle swelling |
| -statin | Statin | atorvastatin, simvastatin | Report unexplained muscle pain or weakness |
| -prazole | Proton pump inhibitor | omeprazole, pantoprazole | Give before breakfast |
| -tidine | H2 blocker | famotidine | Reduces stomach acid |
| -azepam, -zolam | Benzodiazepine | diazepam, midazolam | Sedation, slow breathing; fall risk |
| -cillin | Penicillin | amoxicillin | Ask about penicillin allergy first |
| -mycin, -micin | Aminoglycoside (gentamicin) | gentamicin, amikacin | Kidney damage and hearing loss; drug levels |
| -floxacin | Fluoroquinolone | ciprofloxacin | Tendon pain or rupture; separate from antacids |
| -parin | Heparin | enoxaparin | Bleeding (see Lesson 11) |
| -sone, -olone | Corticosteroid | prednisolone, hydrocortisone | High glucose, infection risk; do not stop suddenly after long use |
Exam tip
Not every "-mycin" is an aminoglycoside (erythromycin and azithromycin are macrolides). In the exam, gentamicin is the classic "kidneys and ears" drug.
Diuretics: potassium is the key
- Furosemide (loop diuretic): powerful fluid loss and low potassium. Give in the morning so the patient is not up all night. Watch BP, weight and potassium.
- Spironolactone (potassium-sparing): high potassium. Avoid potassium supplements and salt substitutes unless prescribed.
Drugs with narrow safety margins
Digoxin
Usual range
About 0.5–2.0 ng/mL (heart failure targets are often lower)
Toxicity signs
Nausea, vomiting, loss of appetite, blurred or yellow-green vision, slow or irregular pulse
Nursing point
Apical pulse 1 full minute; hold if below 60 in adults. Low potassium increases toxicity
Lithium
Usual range
About 0.6–1.2 mmol/L (ranges vary)
Toxicity signs
Coarse tremor, vomiting, diarrhoea, confusion, unsteadiness
Nursing point
Keep fluid and salt intake steady; dehydration raises the level
Phenytoin
Usual range
About 10–20 mcg/mL
Toxicity signs
Unsteady gait, double vision, slurred speech
Nursing point
Gum overgrowth: good oral care
Gentamicin
Usual range
Peak and trough by policy
Toxicity signs
Rising creatinine, ringing in the ears, hearing loss
Nursing point
Check kidney function and levels
| Drug | Usual range | Toxicity signs | Nursing point |
|---|---|---|---|
| Digoxin | About 0.5–2.0 ng/mL (heart failure targets are often lower) | Nausea, vomiting, loss of appetite, blurred or yellow-green vision, slow or irregular pulse | Apical pulse 1 full minute; hold if below 60 in adults. Low potassium increases toxicity |
| Lithium | About 0.6–1.2 mmol/L (ranges vary) | Coarse tremor, vomiting, diarrhoea, confusion, unsteadiness | Keep fluid and salt intake steady; dehydration raises the level |
| Phenytoin | About 10–20 mcg/mL | Unsteady gait, double vision, slurred speech | Gum overgrowth: good oral care |
| Gentamicin | Peak and trough by policy | Rising creatinine, ringing in the ears, hearing loss | Check kidney function and levels |
Remember
Ranges differ between laboratories and guidelines. Use your hospital's reference range; the exam tests the direction (too high, too low) and the signs.
Antidotes: learn these pairs
| Drug or poison | Antidote |
|---|---|
| Opioids (morphine, fentanyl) | Naloxone |
| Benzodiazepines | Flumazenil |
| Heparin | Protamine sulfate |
| Warfarin | Vitamin K (phytomenadione); prothrombin complex concentrate for major bleeding |
| Paracetamol overdose | Acetylcysteine (N-acetylcysteine) |
| Digoxin toxicity | Digoxin-specific antibody fragments |
| Magnesium sulfate toxicity | Calcium gluconate |
| Insulin (hypoglycaemia) | Glucose; glucagon if no IV access and unable to swallow |
| Organophosphate poisoning | Atropine (with pralidoxime) |
| Beta-blocker overdose | Glucagon |
| Iron overdose | Deferoxamine |
| Dabigatran | Idarucizumab |
| Malignant hyperthermia | Dantrolene |
Worked example
A post-operative patient on a morphine PCA is very sleepy and breathing 7 times a minute.
First: stop the opioid and support the airway and breathing (stimulate, give oxygen as prescribed, call for help), then give naloxone as prescribed. Recheck often: naloxone can wear off before the opioid, so breathing can slow again.
Emergency drug: anaphylaxis
Signs: sudden wheeze or stridor, swelling of lips or tongue, low BP, hives, after a trigger (often a drug or food).
- 1Stop the trigger (e.g. stop the infusion) and call for help.
- 2Adrenaline IM into the anterolateral thigh. Adult dose is commonly 0.5 mg (0.5 mL of 1 mg/mL); repeat after 5 minutes if needed. Follow your hospital's protocol.
- 3Lie the patient flat with legs raised (sit up if breathing is difficult), oxygen, IV fluids.
Safety
Adrenaline for anaphylaxis is given IM, not as an IV push of the 1 mg/mL strength.
Other common checks
- Nitroglycerin (GTN) sublingual for chest pain: one dose every 5 minutes, up to 3 doses; check BP before each. Never with sildenafil (dangerous fall in BP).
- Metformin: may be held before and after iodinated contrast per policy (risk of lactic acidosis with kidney injury).
- Vancomycin: infuse slowly; a fast infusion causes flushing and rash of the upper body ("vancomycin infusion reaction").
- Antibiotics: take cultures before the first dose when ordered, but do not delay antibiotics in sepsis.
Remember
Key points
Name endings tell you the class. Beta blocker and digoxin: check the pulse. ACE inhibitor: cough, angioedema, potassium. Furosemide lowers potassium; spironolactone raises it. Low potassium makes digoxin toxic. Learn the antidote pairs. Anaphylaxis: adrenaline IM.