Discussion of the Preparation

An aqueous solution of sodium phenobarbital is less suitable due to poor taste and instability. There is discussion regarding the use of alcohol and propylene glycol, as there is insufficient reliable data on the full safety of these substances, particularly in children. Therefore, preference is given to the preparation of a suspension.

Composition

• Phenobarbital 3 g
• Citric acid 0.15 g
• Veegum 3 g
• Na CMC medium viscosity 3 g
• Raspberry essence 6 dr
• Tween 80 0.3 g
• Sugar syrup 100 g
• Concentrated Nipa solution 2.1 g
• Aqua ad 300 ml (320 g)

Method of Preparation

1. Tare a 500 ml beaker and use a mixer to disperse the Veegum in approximately 180 ml of freshly boiled water until no lumps are visible.
2. Add the CMC and disperse again.
3. Add the concentrated Nipa solution and the citric acid and mix. Allow the solution to cool.
4. Triturate 3.3 g of phenobarbital and sieve it. Place 3 g of the sieved powder into a mortar and triturate with the Tween 80.
5. Weigh 110 g of sugar syrup in a tared beaker.
6. Add a small amount of syrup to the phenobarbital and triturate to a homogeneous paste.
7. Add the raspberry essence and further dilute the mixture with sugar syrup while mixing well. Ensure that exactly 100 g of sugar syrup from the beaker is used.
8. Transfer the contents of the mortar as quantitatively as possible into the beaker containing the CMC-Veegum gel while mixing well.
9. Record the weight and measure the remaining amount of water. Rinse the mortar with this water and add the rinsing water to the beaker.
10. Disperse the mixture with the mixer. Transfer everything to a bottle and label with the instructions for use and the statement "shake before use".

Commentary

• The pH value must be between 5.5 and 6 during process control.
• The shelf life of the suspension is three months.
• The phenobarbital must be very fine to prevent the formation of a precipitate of larger crystals; therefore, use the powder form.
• The use of Tween 80 is necessary for proper wetting.