While acting as a depressant to the hepatic function, atropine ea uses no change in the amount of iron in the liver, and only a slight diminution in the quantity of glycogen. Brunton and Delepine (Proceedings of the Royal So ciety, No. 234, '94).
Dilatation of the pupil is a prominent effect of atropine, however introduced into the system, accompanied by tem porary paralysis of the muscle of accom modation.
In its action on the cerebro-spinal system the general effects of atropine resemble those of opium in that it is both an excitant and hypnotic, but the soporific effect is less marked; and coma, if it occurs, must be considered a remote consequence rather than a direct effect of the action of the drug. After large doses insomnia and delirium arise and poisonous doses prolong these effects for hours, and coma gradually supervenes. Headache, vertigo, illusions, hallucina tions, a busy delirium, and sometimes somnolence are produced by large doses. More or less anaesthesia of the sensory centres of the cerebrum. The action on the motor centres and the spinal cord is comparatively slight. The corpora striata participate both in the hypnotic and in the excitant effects. Giddiness and muscular weakness, from inability for exertion, accompany the hypnotic effect, while restlessness and insomnia occur when the hypnosis is overruled by the excitant action. The spinal cord is least of all affected by atropine.
Atropine Poisoning. — Fatalities from atropine are comparatively rare, for the lethal effect comes on very slowly, and generally gives time both for appropriate treatment and for its elimination through the natural channels. One-half grain of atropine has proved fatal, though Harley reports recovery after the ingestion of 1 grains.
The symptoms of poisoning are, in general, those following the use of a large dose (previously described), but more intensified. The action of the heart, however, while increased in fre quency, is diminished in force; the ar terial tension becomes subnormal; the pulse weak and its rhythm disturbed. As the vascular pressure falls, the skin cools, its color fades, and it becomes covered with clammy sweat. The de lirium, at first mild and happy, becomes unpleasant or disagreeable, or may take the character of the delirium of terror, resembling the maniacal type. The respiration becomes feeble, superficial, rapid, and irregular. Disturbance of the
respiratory functions and the impaired action of the heart and blood-vessels cause passive congestion of the lungs and brain. The urine, previously in creased in amount, is diminished or even suppressed from lessened vascular press ure. Post-mortem examination reveals a distension of the right heart and con gestion of the brain, lungs, and abdom inal viscera.
More deaths have followed medicinal doses of atropine than of any other drug; if possible, therefore, other drugs should be substituted for it. Atropine has been used in the following diseases: 1. Neu- ' ralgia and other painful affections. Con sidering the large number of analgesics available, it should be used in the pres ent day in exceptional cases only,—for example, in angina pectoris. 2. Whoop ing-cough and asthma. If the cases are severe and have resisted all other treat ment, atropine may be tried. 3. The same applies to epilepsy. 4. It is very doubtful whether it is of any use in hysteria, paralysis agitans. and other tremors. 5. Chronic constipation. As there are plenty of substitutes, its use should be discontinued. 6. Lead colic. In this disorder the subcutaneous use of atropine has more disadvantages than advantages. 7. Nocturnal enuresis. Great caution is necessary, since large doses are required, as a rule. S. As a cardiac tonic, and in those cases of per manent bradycardia which often end in epilepsy, atropine has been tried without much success in the latter cases, possibly because a slow pulse does not always correspond to a slowly acting heart. Ac cording to Dehio, it may benefit slight cases of cardiac irregularity, but is with out effect in severe ones. J. In night sweats it acts ell; but, although small doses tend to prevent collapse,—which is common in phthisical patients,—larger ones increase the liability to it. To be gin with a dose of a/,, grain is un justifiable in advanced cases of phthisis. 10. In chronic hypersecretion of HCI by the gastric mucosa several observers have found that atropine diminished the secretion, but others deny this. How ever, considering the bad effects of this hyperseeretton on the gastric mucosa, in the present state of our knowledge atropine must still be tried. 11. Some observers state that atropine, given hypo dermically, arrests haemorrhage (hannop tysis, etc.) by its action on the arterioles.