حساب الجرعات
Every formula you need, with examples from the bank.
علم الأدوية وحساب الجرعات
Core formulas
| Formula | Example from the bank |
|---|---|
| Dose = (Desired ÷ Have) × Quantity | Ordered 30 mg; stock 15 mg/5 mL → (30 ÷ 15) × 5 = 10 mL |
| mL/h = total volume ÷ hours | 1000 mL over 6 h → 167 mL/h |
| Drops/min = (volume × drop factor) ÷ minutes | 2000 mL over 12 h, 15 gtt/mL → 30,000 ÷ 720 ≈ 42 gtt/min |
| Weight-based dose = mg/kg × kg | 30 mg/kg/day × 67 kg = 2,010 mg ≈ 2 g/day |
| Fluid allowance = restriction − IV fluids | 1400 mL limit − (50 mL × 4) IV = 1200 mL oral |
| Parkland = 4 × kg × %TBSA | 4 × 62 × 22.5 = 5,580 mL over 24 h |
| ORS for some dehydration = 75 mL/kg over 4 h | 8 kg × 75 = 600 mL |
| MAP = (SBP + 2 × DBP) ÷ 3 · CPP = MAP − ICP | BP 180/65, ICP 25 → MAP 103, CPP 78 mmHg |
| Pulse pressure = SBP − DBP | 142/88 → 54 mmHg |
| Cardiac output = stroke volume × heart rate | 80 mL × 120 = 9,600 mL/min |
| BMI = kg ÷ m² | 63.5 ÷ 1.83² ≈ 19 (normal) |
Conversions
- 1 g = 1,000 mg · 1 mg = 1,000 mcg · 1 L = 1,000 mL · 1 kg = 2.2 lb
- 1 tsp = 5 mL · 1 tbsp = 15 mL · 1 oz = 30 mL · 1 inch = 2.54 cm
- Maintenance fluids for children (per day): 100 mL/kg for the first 10 kg + 50 mL/kg for the next 10 kg + 20 mL/kg for each kg above 20.
Abbreviations
| Abbreviation | Meaning |
|---|---|
| OD / daily · BID · TID · QID | Once · twice · three times · four times a day |
| q4h · PRN · stat | Every 4 hours · as needed · immediately |
| AC · PC · HS | Before meals · after meals · at bedtime |
| PO · SL · SC · IM · IV | By mouth · sublingual · subcutaneous · intramuscular · intravenous |
If a calculation needs an unrealistic number of tablets (e.g., 100 tablets), or a dose looks unsafe, do not give it — clarify with the prescriber.
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67 سؤالاً بنمط الاختبار في علم الأدوية وحساب الجرعات، مع شرح لكل خيار. حساب مجاني بدون بطاقة.
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