ࡱ> fhg'` {bjbjDD i6&&~4" " " " $ 666P,< BSh:4444h%h%h%RRRRRRR$UhXVR /$$|//R" " 44R333/" 84r R4R3/R33*LZ  " Q4 PC76 0BOn5RS0BS'PhXN1hX Q Q8hX AQh%8(3:*+Bh%h%h%RRP3dh%h%h%BS//// dn D n  " " " " " "   9 August, 2010 Greg Williams Therapeutic Group Manager PHARMAC P.O. Box 10 254 Wellington 6143  HYPERLINK "mailto:Greg.Williams@pharmac.govt.nz" Greg.Williams@pharmac.govt.nz Dear Greg RE: Phenobarbitone sodium oral liquid formulation Following discussions at our Telepaediatrics meetings we propose the following phenobarbitone sodium oral liquid formulation for inclusion in the New Zealand Pharmaceutical Schedule as the only subsidised formulation: Phenobarbitone Sodium 10mg/ml Oral Liquid Phenobarbitone sodium powder 400 mg Glycerol 4 mL Water to 40 mL Storage: Fridge Expiry: 28 days This formulation was manufactured and tested for physicochemical stability by researchers at the School of Pharmacy, University of Auckland, with the results published in 2008.1 Key points from the study results were: pH: At a concentration of 10mg/mL (1%), phenobarbitone sodium should be maintained above pH 8.6 to prevent precipitation. Therefore acidic syrups and flavouring agents should be avoided in the manufacturing process due to their potential for pH reduction. Glycerol, which has a pH of 5.25, has been included at a concentration of 10%. It was suggested that higher concentrations of glycerol may result in precipitation of phenobarbitone sodium. Concentration: When stored in both refrigerated and room temperature conditions the formulation maintained 100% concentration after four weeks. Taste: The unpleasant taste of phenobarbitone sodium was disguised by the addition of flavouring agents, especially lime, lemon, and orange flavours. However, as mentioned, the addition of these agents was not recommended for stability reasons. Expiry date: An expiry date of 28 days is appropriate for this formulation. Additional comments from our own research: Glycerol: Glycerol has antimicrobial properties when used in concentrations < 20%.2 This further endorses the inclusion of glycerol at a concentration of 10%. Osmolarity: A 2.6% v/v aqueous solution of glycerol is stated to be iso-osmotic with serum.2 Based on first principles the osmolarity of a 70% solution of glycerol is calculated to be around 7,600 millosmoles/L. For a 10% solution the osmolarity is around 1,090 milliosmoles/L. It should be noted that there is often a difference between calculated and measured solution osmolarities.3 In summary: From the results of the study and our own findings we recommend the above formulation with an expiry date of 28 days when stored in a fridge. If necessary, any unpleasant taste of the oral solution could be disguised by the addition of lemon or orange flavouring at the time of administration e.g. ice blocks or cordial drink. The advantages of our proposal, for the inclusion of this phenobarbitone sodium oral liquid formulation in the Pharmaceutical Schedule, is nation-wide standardisation of a researched and validated formulation. The inclusion of the calculations in the formula will enhance medication safety by reducing the potential for calculation errors at the compounding stage, thus increasing patient safety. Please contact us if you have any queries regarding the proposed formulation. Kind regards Brenda Hughes Convenor, Pharmacist & Therapeutics Special Interest Group The Paediatric Society of New Zealand. Letter prepared by: Brenda Hughes, Specialist Paediatric Pharmacist. Reviewed and approved by: Dianne Wright, Clinical & Advisory Paediatric Pharmacist, Taranaki Base Hospital. Barbara Robertshawe, Clinical Pharmacist, Neonatal Unit, Christchurch Womens Hospital. Jacqui Reynolds, Team Leader, Womens & Childrens Health, Middlemore Hospital. Dr Simon Rowley, Consultant Paediatrician/ Neonatologist, Auckland District Health Board Caroline De Luca, Senior Paediatric Pharmacist and Formulary Pharmacist, Auckland City Hospital. Andrew Sutton, Team Leader Womens and Childrens Health, Auckland City Hospital. Jenny Crawford, Pharmacist, Child Woman and Family, Waitakere Hospital. References: 1. Garg S, Svirskis D, Myftiu J, et al. Properties of a Formulated Paediatric Phenobarbitone Oral Liquid. J.Pharm.Pract. 2008; 38:28-31. 2. Rowe RC, Sheskey PJ and Weller PJ (eds). Handbook of Pharmaceutical Excipients. (4th ed). London: Pharmaceutical Press, 2003. 3. Wade A (ed). Pharmaceutical Handbook (19th ed). London: Pharmaceutical Press, 1980. William Allan, President, New Zealand Hospital Pharmacists Association.  HYPERLINK "mailto:William.Allan@hawkesbaydhb.govt.nz" William.Allan@hawkesbaydhb.govt.nz Paula Ferguson, Dispensary Manager, Auckland City Hospital.  HYPERLINK "mailto:Paula.Ferguson@adhb.govt.nz" Paula.Ferguson@adhb.govt.nz     THE PAEDIATRIC SOCIETY OF NEW ZEALAND Secretariat: Email:Denise Tringham P O Box 22 234 Wellington 6441 Tel: (04) 938 4827 Fax: (04) 976 4827 psnz@paradise.net.nz  Health of our children: Wealth of our nation  hi   8 D [ g K L M N x ʫٝxtxpxpxdXh1hSH*^JaJh\hSH*^JaJh|Wh2 h1h1h1h15h1hS^JaJh1h1^JaJh\hS5>*^JaJh\hS0J^JaJ#jh\hSU^JaJjh\hSU^JaJh\hS5^JaJh\hS^JaJhHql^JaJhSh$G"&@HXh  ( K o $Ifgdxel$<$Ifa$gdxelZ ]Z gdSgdS~BFzo p M N v 3 kb]]]L & F$ d*$gdSgdSZ ]Z gdSkkd$$IfTl t0644 laT<$Ifgdxel$Ifgdxel 3 B /;CD+,RSTUa24ao8궦hE(o^JaJhFW^JaJh1h9y^JaJh)-^JaJh1^JaJhS^JaJh;<5^JaJh\hSH*^JaJh_ hS^JaJh\hS5^JaJh\hS^JaJh1h1^JaJ43 1TUa9: d*$gdL & F% d*$gdSgdS & F$ d*$gdS89  !Pl%rs23LM{|}׼꜐v#jHhxh?|^U^JaJh?|^^JaJjh?|^U^JaJhS^JaJh\hS5^JaJh\hSH*^JaJh>^JaJhEYhSCJ^Jhn<^JaJh1^JaJh1h1^JaJh\hS^JaJh\h)-^JaJ,   !Rlf pQ234| & F&gd?|^ 0^`0gdS L^`Lgd1 L^`Lgd>gdS,-]^_z{|}~ļwswswsws`Wh$G5OJQJ%jh$G5OJQJUmHnHuhNajhNaU h1hgCh\h6^JaJhxh60J^JaJ#jWhxh6U^JaJjh6U^JaJh6^JaJhS^JaJh\hS^JaJh1^JaJh?|^^JaJjh?|^U^JaJhxh?|^0J^JaJ||}~  !Sn#$If !Sn#$If$ x$Ifa$  $Ifd 0gdgCgdV. ^ gd?|^678:=?@ABz{ɹɹ׵ h1hgChNahYh|ljh$GUmHnHuh$Gh$G5B*CJOJQJphh$GB*CJOJQJphh$G5OJQJh$G5B*CJ(OJQJphh$G5B*CJ$OJQJph"789hb !ekdJ$$If\u+#a  $If  $If !Sn#$If  !Sn#$If 9:>?@ABCDEFGHwxyz{