ANEURINE (thiamine) 



13. EFFECT OF EXCESSIVE DOSAGE WITH ANEURINE 



According to C. L. Steinberg,^ daily doses of 100 /zg. of aneurine 

 given to rats caused sterility in the second generation females, whilst 

 daily doses of 200 and 400 /xg. resulted in the appearance of a toxic 

 factor in the milk of the third generation females and in complete 

 failure of lactation respectively. This observation was confirmed by 

 M. B. Richards,^ who found that failure of lactation was more severe 

 the higher the intake of aneurine, and that litters from does with a 

 high aneurine intake (plus calcium carbonate) failed to survive, were 

 in a poor condition or showed convulsive fits due to pyridoxine de- 

 ficiency. Excess of aneurine, in fact, appeared to precipitate pyri- 

 doxine deficiency. L. R. Cerecedo and L. J. Vinson, ^ on the other 

 hand, failed to find evidence that amounts of the order of 625 to 700 

 /xg. per day had any harmful effects on the fertility or lactation of 

 rats. According to C. Mano,* the respiration of mice was stimulated 

 by small doses, whilst respiratory arrest and chronic cramps were 

 produced by large doses. 



C. L. Steinberg ^ also reported that, in humans, overdosage with 

 aneurine may give rise to herpes zoster, and C. A. Mills ^ and Z. A. 

 Leitner ® found that an intake of more than 5 mg. per day produced 

 symptoms of hyperthyroidism, e.g. nervousness, tremors, tachy- 

 cardia and sweating. It was suggested that these were due to over- 

 dosage or, more correctly, to supers at urat ion. When the vitamin 

 was withdrawn, the nervousness and other sjmiptoms disappeared. 



Several cases of sensitivity resembling allergic reactions have also 

 been reported ; ^' "^ in at least one instance the patient was desensitised 

 by the conventional procedure. As, according to F. Kalz,^ injection 

 of aneurine hydrochloride intradermally invariably causes a histamine- 

 like reaction, the intradermal test cannot be used to test sensitivity 

 towards aneurine. Anaphylaxis plays no part in aneurine toxicity as 

 seen in rabbits,® but the injection of a sensitising dose of 100 mg. 

 increased the resistance of the animals to toxic injections of the 

 vitamin, increasing the lethal dose from 126 to 238 mg. per kg. 

 H. Molitor ^^ was imable to sensitise dogs and guinea-pigs so that 

 anaphylactic phenomena appeared. Anaphylactic shock has been 

 reported in man.^^ 



Aneurine is usually regarded as non-toxic. N. Joliffe,^^ for instance, 

 observed no toxic effects in over 3000 patients ; he also reported that 

 Borsook treated seventy patients for three years with 100 mg. of 

 aneurine hydrochloride per day without untoward results. It seems 

 to be generally accepted that aneurine can safely be given by mouth, 

 but should be given by injection only in severe intestinal dysfunction 

 and acute beriberi. In the rare instances in which parenteral 



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