1. Paediatric Prescribing and Common Medications Diana Mowbray Paediatric Clinical Pharmacist Rotherham NHS Foundation Trust

2. Things to Consider When Prescribing Child’s age and weight (Kg) / surface area Allergy status Obesity / underweight Immune status How to get the drug into the body

3. Common Drugs Antipyretics Pain killers Antibiotics Inhalers Anti-epileptics Anti-reflux medications Fluids

4. Antipyretics Paracetamol –15mg/Kg 4hrly Ibuprofen –1-3/12 5mg/Kg TDS/QDS –3/12 – 1yr 50mg TDS/QDS –1-4yrs100mg TDS –4-7yrs150mg TDS –7-10yrs200mg TDS –10-12yrs300mg TDS –>12yrsup to 400mg TDS/QDS

5. Oral Pain Killers Paracetamol –Can go up to 20mg/Kg in > 1/12 –Max 90mg/Kg/day –Can use a loading dose Ibuprofen –As for antipyretics (max 30mg/Kg/day) Diclofenac –Up to 1mg/Kg (max 50mg) TDS

6. Oral Pain Killers contd Codeine –0-12yrs 0.5-1mg/Kg every 4-6hrs –> 12yrs30-60mg every 4-6hrs –Max 240mg daily Morphine –1-12/1280-200micrograms/Kg 4hrly –1-2yrs200-400micrograms Kg 4hrly –2-12yrs200-500micrograms/Kg 4hrly max 20mg –>12yrs5-20mg 4hrly

7. Antibiotics.Penicillins eg amoxicillin Cephalosporinseg cefotaxime Macrolides eg erythromycin Aminoglycosides eg gentamicin Trimethoprim Metronidazole

8. Inhalers Ipratropium bromide –Can be useful in young babies for wheeze Salbutamol –Useful in all ages for wheeze – variable response in young babies Beclometasone –Useful at step 2 upwards of the asthma management guidelines

9. Anti-epileptics Carbamazepine Sodium valproate Phenytoin Phenobarbitone Midazolam Clobazam Diazepam

10. Anti-reflux medications Gaviscon infant sachets Ranitidine Domperidone Omeprazole / Lansoprazole

11. Fluids Sodium chloride 0.45% with Dextrose 5% - basic children’s fluid Dextrose 10% - basic neonatal fluid May be with or without potassium chloride dependent on clinical situation

12. Calculations Always best calculated against weight / surface area where possible NSF for children recommends all calculations should be documented in patient’s notes

13. Anti-reflux medications A 5 week old term baby (4.13Kg) presents with GORD. They have been treated with Gaviscon infant sachets at home. The child is still vomiting and not gaining weight. You are asked to prescribe oral Ranitidine and Domperidone What doses would you prescribe?

14. Anti-reflux medications Ranitidine – 1mg/Kg TDS –Prescribe as 4.1mg or 4mg TDS Domperidone – 200- 400microgram/Kg 3-4 times a day –Prescribe as 830-1650micrograms 3-4 times a day (0.83-1.65mg)

15. Anti-reflux medications Ranitidine comes as 75mg/5ml solution –Calculate the volume required –0.27ml Domperidone comes as 1mg/ml suspension –Calculate the volume required –0.83-1.65ml

16. Anti-epileptics A 7 yr old (21.7Kg) is admitted with generalised seizures and needs to be started on sodium valproate 200mg/5ml What dose would you prescribe initially and what dose would you anticipate the patient being maintained on? What volumes of medication will this mean needs drawing up?

17. Sodium Valproate Initiate on 5-7.5mg/Kg BD –108.5-162.75mg BD –Ideally prescribe 110-165mg BD –2.7-4.1ml BD Maintenance is 12.5-15mg/Kg BD –272-324mg BD –6.6-8.1ml BD

18. Lamotrigine A 3yr old (14.5Kg) known epileptic on sodium valproate 3.8ml BD for 8 months is admitted with uncontrolled seizures. You are asked to prescribe Lamotrigine in addition What dose will you prescribe?

19. Lamotrigine Lamotrigine interacts with sodium valproate (inhibits hepatic catabolism) and so a lower dose is required than would be if it was used with any other anti-epileptic Initial dose: 150microgram/Kg OD for 14 days, increasing gradually to a usual maintenance of 1-5mg/Kg in 1-2 divided doses (max 100mg) Calculate the doses required

20. Lamotrigine Initial dose is 2.2mg (2.175mg) This can be achieved by dissolving a 5mg tablet in 5ml water and giving 2.2ml Maintenance is 14.5-72.5mg/day

21. Other problem This child is also on a low dose of sodium valproate for it’s weight. 3.8ml = 152mg = 10.5mg/Kg/dose Usual maintenance is 12.5-15mg/Kg/dose This is probably due to weight increase in the last 8 months and should be adjusted accordingly (perhaps before considering an additional drug!)

22. Prescribing problems A patient arrives with the following list of medication from mum (who has left the drugs at home). Which ones would you be confident to prescribe? Baclofen 20ml TDS Glycopyrollate 4ml QDS Clonazepam 3.5ml BD Sodium Valproate 10ml BD Levetiracetam 3ml BD Alimemazine 7.5ml ON

23. Prescribing Problems Baclofen only comes as 5mg/5ml Glycopyrollate is only available as a “special” Clonazepam is only available as a “special” Sodium valproate only comes as 200mg/5ml Levetiracetam only comes as 100mg/ml Alimemazine is available in 2 strengths

24. Neonatal infusions A 760g neonate requires a dopamine infusion to run at 7.5microgram/Kg/minute The infusion is prepared as 30mg dopamine in 50ml of 10% dextrose What rate should the prescription state for the pump to run at?

25. Neonatal infusions 0.76Kg x 7.5micrograms/Kg/min = 5.7micrograms/min 5.7micrograms/min x 60mins = 342micrograms/hour 30mg dopamine in 50ml contains 30 x 1000 / 50ml = 600micrograms/ml The infusion needs to run at 342 / 600 = 0.57ml/hour

26. Common problems Decimal points may not be clear –Trailing zeros eg 2.0 may be mistaken for 20 –Missing zeros eg.5 may be mistaken for 5 Use of abbreviations to be avoided Concentration errors when only a volume is prescribed Frequencies / times of administration not prescribed on kardex = drugs not given

27. Common problems Not reading all the information in BNFC to find an appropriate dose –Mixing up of routes and doses –Mixing up of reason for giving and doses –Using correct age range (especially in neonatal period) for doses and frequencies

28. Quick Quiz How many mg of adrenaline in 1ml of –1 in 1000? –1 in 10,000? How many mmol of sodium in 500ml of 0.45% sodium chloride with 5% glucose? A 10Kg child requires 0.2mmol/Kg (50mg/Kg) magnesium sulphate. How much of a 50% solution do you need?

29. Answers 1g in 1000ml = 1mg/ml 1g in 10,000ml = 0.1mg (100microgram) /ml 0.9% sodium chloride contains 150mmol Na/L = 75mmol in 500ml = 37.5mmol in 500ml of 0.45% 10Kg x 50mg/Kg = 500mg. A 50% solution contains 50g/100ml = 50,000mg/100ml = 500mg/ml

30. Questions ?