Sodium bicarbonate Ephedrine

Method. The tablet or capsule containing ephedrine is pulverized and mixed with 70 ml of ethanol at 40 °C for 20 min with magnetic stirring. The resulting solution is filtered and the clear filtrate is diluted to 100 ml. 1 ml of this solution is treated with 5 ml of ethanol, 5 ml of acetone, 1 -2 ml of a solution of DNS-C1 (2 mg/ml in acetone) and 2 ml of a solution of sodium bicarbonate (10 mg/ml in water). The solutions are shaken and placed in the dark for 1 h. An aliquot portion of the resulting mixture is analyzed by TLC on plates of silica gel using benzene-ethanol-acetic acid (90 10 1) as solvent. An alternative procedure for ephedrine has been discussed earlier [123]. 

Urinary acidifiers may increase elimination of ephedrine, and urinary alkalinizers may decrease the elimination of ephedrine. Ephedrine is chemically incompatible with sodium bicarbonate and the two should not be used together. 

SYMPATHOMIMETICS ANTACIDS-SODIUM BICARBONATE Possibly t ephedrine/ pseudoephedrine levels Alkalinising urine 1 excretion of these sympathomimetics Watch for early features of toxicity... 

Aluminium hydroxide may possibly cause a more rapid onset of pseudoephedrine activity (but this needs confirmation). Any interaction seems unlikely to be clinically significant. Similarly, the effects of kaolin on absorption are small and unlikely to be clinically important. For the effect of sodium bicarbonate on pseudoephedrine and ephedrine, see urinary alka-Iinisers%(p.l277). 

Alkalinisation of the urine (e.g. by sodium bicarbonate) causes retention of ephedrine and pseudoephedrine by the kidneys, leading to the possible development of toxicity (tremors, anxiety, insomnia, tachycardia). Acidification of the urine (e.g. with ammonium chloride) has the opposite effect. 

When the urine was made aeidie (pH of about 5) with ammonium chloride, the exeretion of ephedrine in the urine of three healthy subjects was two to fourfold higher than when the urine was made alkaline (pH of about 8) with sodium bicarbonate. ... 

The interaction between ephedrine or pseudoephedrine and urinary alkalinisers are established but reports of adverse reactions in patients appear to be rare. Be aware that any increase in the adverse effects of these drugs (tremor, anxiety, insomnia, tachycardia, etc.) could be due to drug retention brought about by this interaction. Acetazolamide makes the urine alkaline and would be expected to interact with ephedrine and pseudoephedrine in the same way as sodium bicarbonate. 

To a solution containing about 0 15 g of ephedrine in 10 ml of water, add sufficient sodium bicarbonate to saturate the solution. Then add a total of 1 ml of acetic anhydride in three approximately equal portions, shaking vigorously after each addition and using due care in releasing pressure developed by carbon dioxide evolution. Allow the reaction mixture to stand fifteen minutes, acidify carefully with dilute sulphuric acid and extract the acetyl-ephedrine immediately with 15-ml portions of chloroform. Wash each extract successively with a dilute solution of sodium bicarbonate, evaporate, dry at 105, cool and weigh. C12H17O2N X 0-9731 -- ephedrine hydrochloride. 

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