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 ON DIGITALIS. 
 
 A LBOTURB DBLIVBRBD BEPORB THB MATERIA MBDIOA 
 
 CLASS. MOILL UNTVBRSITY, MONTBBAL, 
 
 NOVBMBBB, 1884. 
 
 BY 
 
 JAMES STEWART, M.D., 
 
 Professor of Materia Mbdica awd Therapeutics, McGill University, 
 
 pfiVsiciAN to the Montreal Dispensary, and Director of the 
 
 University Dispensary for Diseases of the Nervous System. 
 
 GAZETTE PRINTING COMPANY. 
 
 1884. 
 
 
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REPRINTED PROM TTTE " CANADA MEDICAL & SURaiCAL JOURNAL." 
 
 DECEMBER, 1884. 
 
 ti 
 
 DIGITAJuIS. 
 
 By JAMES STEWART, M.D., 
 
 Professor of Materia Modica and Therapeutics, McGill University ; Phy- 
 
 sician to the Montreal Dispensary, and Director of the University 
 
 Dispen-ary for Diseases of the Nervous System. 
 
 Gentlemen,- The leaves of the digitalis plant contain three 
 glucosides, eaoh ol which possesses active cardiac physiological 
 actions. These are digitalin, digitalein and digitoxin. 
 
 In addition there is a fourth glucoside called digitonin desti- 
 tute of any cardiac properties, but having an action very similar 
 to saponin, the active principle of senega root. Digitalis leaves 
 also contain a resin w'lich closely resembles picrotoxin in its 
 actions. 
 
 The active principles commonly known as Qu^venne's and 
 Nativelle's digitalino have been proved to be mixtures of the 
 various glucosides above mentioned. None of the glucosides 
 possess any advantage over a preparation of the leaves, and 
 owing to the great dilHculty in isolating them it is always pre- 
 ferable to use a tincture or infusion of the leaves. 
 
 Pharmaoology. — There is no medicinal agent whose physio- 
 logical actions it is more nnportant tha*^^ you should thoroughly 
 understand than digitalis, ior when used in proper cases and in 
 proper doses it is capable ol accomplishing a great deal of good. 
 Although not, except in very exceptional cases, a curative agentf 
 in the narrowest sense of that terra, it is capable in many cases 
 of not only giving great rcliel, but of prolonging life, frequently 
 
 ♦Lecture de'ivered before the Materi I Medica class, November, 1884. 
 tin cases of acute dilatation of the o irt occurring as the result of anaemia it is 
 a directly curative agent. 
 
± 
 
 for very many months, and at times even for many years. 
 The good that is obtained ))y mercury in syphilis, by salicylic 
 acid in acute rheumatism, hy ((uinine in malarial fevers is no 
 more striking than the action wliicli digitalis possesses in steady- 
 ing and contracting an irrogul.ir and dilated heart. 
 
 Digitalis preparations have a disagreeable bitter taste, and 
 when taken in large medicinal doses may give rise to nausea 
 and vomiting and even to purging. The last effect, however, 
 is very unusual. 
 
 The active constituents diffuse readily into the blood, but 
 what if any influence they exert on it is not known. 
 
 Action on the Circulation. — The effect of small medicinal 
 doses (10 minims of the tincture every twelve hours) of digi- 
 talis is to make the heart beat with an increased vigour. The 
 left ventricle especially beats more powerfully. Coupled with 
 this increased vigour of the heart's contractions, there is a sli^jfit 
 rise in the blood pressure, which has the direct effect of sending 
 more blood to the ventricles and the indirect effect of further 
 stimulating them in their contractions. If larger medicinal 
 doses are administered, we have in addition to an increase in 
 the effects already described, a slowing of the heart. The ven- 
 tricles now beat not only more vigorously, but also slower. This 
 slowing from full medicinal doses may amount to forty or even 
 fifty beats per minute, but it is only in cases of cardiac failure 
 that such a marked reduction takes place, and then only when 
 the patient is confined to bed. Slight exercise readily quickens 
 the pulse reduced by digitalis. That digitalis can slow the 
 movements of a healthy heart to a considerable extent there is 
 no doubt, but just to what extent it can do this, short of too 
 high doses, I am not able to tell you. Some people's pulses 
 are much easier reduced than those of others. The pulse of 
 the feeble is much more easily reduced than the pulse of the 
 robust. It has very little power in reducing the pulse of fever. 
 If the temperature is high it practically may be said to have no 
 influence at all. The reason of this will be referred to presently, 
 when I come to discuss through what mec hanisms it produces its 
 different efiects on the circulation. If the dose of digitalis be 
 
 ■T 
 
±' 
 
 I • 
 
 '5 
 
 still iiicrcasdl, tlio vigour of the contractions becomes still 
 ;:;reater and the slowin;^ more decided until finally the ventricles 
 come to a standstill in contraction. 
 
 A state of tetanus of the cardiac muscle is induced ; this is 
 (juite different from the effects of aconite which also slows the 
 heart, and finally brings it to a standstill in dilatation. No 
 better method can be employed to demonstrate the action of 
 digitalis on the heart than to take a frog and bring its heart to 
 a standstill in dilatation by injecting aconite. When this has 
 happened, if we inject digitalis the distended ventricle slowly 
 recovers itself, and soon returns to its normal condition. If we 
 still continue injecting digitalis the systole becomes longer and 
 the diastole less complete, especially at the apex which remains 
 white and firmly contracted. This gradually extends over the 
 whole ventricle, the heart finally comes to a standstill in firm 
 contraction. 
 
 VViien either digitalis or aconite are given in such doses as to 
 produce standstill of the heart, the pulse becomes quick and the 
 blood pressure falls. 
 
 " In aconite poisoning the aortic pressure falls because the 
 over distended ventricle is unable to contract upon its contents. 
 Each contraction only sends a small quantity of blood from the 
 upper portion of the ventricle. In digitalis poisoning the aortic 
 pressure falls, because the over-contracted ventricle permits but 
 little blood to get into it and can consequently send but little 
 tonvard. The result is similar in both cases, but the cause in 
 one case is just the reverse of that in the other." — Balfour. 
 
 The action of digitalis on the circulation in full medicinal 
 doses may be summarized as follows : — 
 
 1. It makes the ventricles beat more powerfully. 
 
 2. It makes them beat slower. 
 
 3. It contracts the arterioles. 
 
 4. It raises the blood pressure. 
 
 These effects take place even after the vagi are divided and 
 the spinal cord destroyed. It therefore follows that they are 
 due (necessarily foi the most part) to a direct action on the 
 structures of the heart itself and on the vessels. This is further 
 
6 
 
 confirmed by the fact that when digitalis is directly applied to 
 the isolated frog's heart it slows and renders its movements more 
 j)owerful. 
 
 The increased vigour of the contraction is duo to a stimulation 
 of the intracardiac motor ganglia, while the slowing is princi- 
 pally brought about by stimulation of the peripheral termina- 
 tions of the vagus in the heart. Digitalis also has a stimulat- 
 ing action on the vagus centre in the medulla. 
 
 Dr. Lauder Brunton has quite recently shown that the reason 
 the pulse of fever is not slowed by this drug is that the in- 
 creased temperature has a paralyzing effect on the inhibitory 
 influence of the vagus on the heart. The cause of the contrac- 
 tions of the arterioles has been a very much disputed point, and 
 even yet it is not definitely settled. Some maintain that it is 
 owing to stimulation of the central vaso-motor centre or centres, 
 while others ascribe it wholly to a stimulation of the vaso-motor 
 fibres in the blood vessels. That the latter is a factor in the 
 production of the contraction there appears to bo no doubt, but 
 that the former is the principal agent in the causation seems 
 very probable. 
 
 It follows as a result of the increased contractions and the 
 marked resistance to the blood stream by the contracted arter- 
 ioles, that the aortic pressure is increased. 
 
 The quickening of the pulse brought about by poisonous 
 doses of digitalis is due to paralysis of the inhibitory fibres of 
 the vagus and the final fall in the blood pressure is due to the 
 arteries being imperfectly filled, owing to the contracted state 
 of the heart allowing but little blood to get into it. 
 
 Action on the Temperature. — It is generally admitted that 
 digitalis has some influence in reducing a febrile temperature. 
 It has been experimentally shown by Ackermann, that after it 
 raises the pressure in the arteries, it lowers the temperature in 
 the vena cava, and at the same time raises the temperature of 
 the external parts. It diminishes the internal temperature, 
 and increases the external or surface temperature. It is only an- 
 tipyretic from its action on the circulation. It is not antipyretic 
 in the same sense that quinine and salicylic acid are antipyretics. 
 

 Action on the Nervous Si/stem. — Any efFcct producod by 
 digitiilis on the nervous system is indirectly brought about by 
 it3 inlluenco on the circulation. From full medicinal doses it is 
 not uncommon to hear |iaticnts complain of headache, a band 
 like feeling around the forehead, dizziness and also of colored 
 vision, together with a sense of faintuess, nausea or even actual 
 sickness. 
 
 Action on the Secretion of Urine. — Digitalis has very little 
 influence in increasing the quantity of urine in health, but in 
 cardiac disease attended with dropsy, where there is a dimin- 
 ished outflow owing to the failing heart, it then acts powerfully 
 as a diuretic. The diuretic power is solely due to its influence 
 on the blood pressure. In order to bring about the full diuretic 
 eifects of digitalis it is necessary to give it in full doses. The 
 effect of small and even of moderate doses is to increase the 
 general blood pressure, including the pressure in the arterioles 
 of the kidneys. While the general pressure is increased the 
 qnantity of urine is not increased. After, however, a certain 
 quantity of digitalis has been introduced into the blood, the 
 pressure in the arterioles of the kidneys gives away with the 
 result of a rapid and great increase in the quantity of urine. 
 This may last for several days, depending on the amount ad- 
 ministered. If the drug is still continued, the fall in pressure 
 which commenced in the arterioles of the kidney, extends 
 throughout the whole arterial system with the result of a 
 marked decrease in the secretion of urine. 
 
 It follows from this that there are three stages in the action 
 of digitalis on the arterioles of the kidneys, and each separate 
 action is attended by a difference in the amount of urine secreted. 
 
 1. From the action of small doses (tonic) we have a general 
 increase of the arterial pressure. This stage is not attended by 
 an increase in the quantity of urine. 
 
 2. From the effects of large medicinal doses when continued 
 for two or three days, we have a fall in the arterial pressure in 
 the kidneys, while the increased pressure throughout the rest of 
 the arterial system remains. The result of this action is a great 
 increase in the quantity of urine. 
 
8 
 
 i . When the drug is pushed until the fall in the arterial 
 pressure which commenced in the kidney arterioles has extend- 
 ed so to take in the -whole of the arterial system, there is a 
 marked decrease in the quantity of urine. 
 
 Uses. — The great use of digitalis is in cases of heart failure, 
 especially in cases of heart failure occurring as the result of 
 organic changes in the valves of the heart. It is also useful be- 
 fore actual or pronounced failure has set in. If given in proper 
 doses it is 1 'e to delay, often for a long period, the appearance 
 of failure. 
 
 It makes but little difference what particular orifice may be 
 narrowed or leaking, whether it is the mitral or aortic, digitalis 
 is indicated. It certainly is more eifecacious in some conditions 
 than others, but in a general way the truth of the statement 
 that it is indicated in all forms of heart failure is practically 
 .correct. 
 
 To have clear ideas as to what digitalis can do in restoring 
 a failing heart it is necessary that you should understand what 
 cardiac failure means, and how it is brought about as the result 
 of a valvular lesion. 
 
 I have here the heart of a man, who died a few days ago 
 from the effects produced by incompetence of his aortic valves. 
 Through the kindness of Dr. R. L. Macdonnell he has been un- 
 der my care at the University Dispensary for the diseases of 
 the nervous system for the past seven months. During this 
 time I had repeated opportunities of observing the marked re- 
 lief that he obtained from digitalis. I will first point v.ut the 
 differences between this heart and a normal heart, and after- 
 Avards show how these differences came about, and finally I will 
 refer to the influence digitalis has in preventing and relieving 
 such changes, and what particular influence it had in relieving 
 the symptoms and delaying the end of the case under considera- 
 tion. By adopting this method I think I can make the actions 
 and uses of digitalis plain to you. 
 
 The man at the time of his death was 35 years of age. Since 
 his fifteenth year he had five distinct attacks of acute rheuma- 
 tism. He distinctly remembers that his " heart was affected " 
 
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 during the first seizure, but it never gave him any trouble until 
 four years ago. This was sliortly after his fifth and last attack. 
 We have here a period of twenty years during which he un- 
 doubtedly had a heart lesion, but it is only during the past four 
 years that he suffered from the effects of this lesion. The com- 
 pensation during the first sixteen years of the life of the dis- 
 eased heart was so perfect that it gave rise to no marked symp- 
 toms. Four years ago, however, this compensation began to 
 fail, and we have from this time onwards a history of all that 
 results from such failure. 
 
 You see that the aortic valves are badly deformed and their 
 surfaces studded with a great number of vegetations.* You 
 can readily understand how incompetent these valves were dur- 
 ing life to fulfill their functions of closing the aortic orifice. On 
 further examining the heart we find it greatly enlarged, and 
 that this enlargement is due for the most part to hypertrophy of 
 the muscular fibres of the left ventricle. In addition to an in- 
 crease in the thickness of the ventricular walls, we have also a 
 great increase in the size of its cavity. The left ventricle 
 is both hypertrophied and dilated. For our purposes there is 
 no need of noticing any further changes, with the exception of 
 dilatation of the mitral valve, present in this heart. I will now 
 endeavour to explain how these different pathological conditions 
 were induced. 
 
 The thickening, the vegetations and the deformity of the aortic 
 valves were caused by rheumatic inflammation of their structures 
 during the first and probably also during the subsequent attacks 
 of acute rheumatism. As a result of the incompetency of the 
 valves, the left ventricle receiv^ed during its dilata'^i'^n blood 
 from two sources, in pla.^e of from one — from the aorta as well 
 as from the left auricle. The result was an over-filling of the 
 ventricle. The immediate result of the over fiUing was dilata- 
 tion of the ventricular cavity. This dilatation, however, could 
 only for a very short time relieve the altered conditions. If 
 it were all that had taken place the man would not have lived 
 
 •About a year iigo he was suddenly seized with left hemiplegia, due as was 
 proved at the posi-mortem by Dr- Sutherland to plugging of his right middle cerebral 
 artery by an embolus carried from his warty aortic valves. 
 
10 
 
 at tlio longest more than a few weeks. What did take place 
 was an hypertrophy of the muscular fibres of the left ventricle, 
 and it was this increased power of the ventricular muscle that 
 enabled the circulation to be carried on in spite of the leaking 
 valves. The causes of the three prominent changes in the 
 heart are plain. They may be thus summarized : 1st. The 
 valvular distortion, &c,, is the result of the rheumatic in- 
 flammation of the endocardium. 2nd. The dilatation of 
 the ventricle is owing to it receiving an undue supply of 
 blood into its cavity. 3rd. The hypertrophy is the result of 
 the increased efforts made by the heart to overcome the dilating 
 powers of the column of blood. We have finally to enquire, 
 what brought about the cardiac failure in this heart ? Why 
 did the hypertrophied ventricle fail at last to propel the blood 
 forward ? In all cases like the one we are considering there 
 arrives a time when the heart is no longer able to do its work. 
 A very frequent reason of this failure is a degeneration of the 
 muscular structure as a result of the long continued over-work, 
 or it may be brought about acutely as the result of a severe 
 illness, especially when attended by a high temperature. In 
 the heart before us, the prominent factor in bringing about 
 failure was not degeneration of its muscular structure, for on 
 closely examining it you will find its walls firm, and not, at least 
 to the naked eye, the seat of advanced fatty degeneration. 
 The main factor in the production of the failure was a purely 
 physical one. In cases of aortic incompetency dilatation is 
 ever slightly in advance of hypertrophy. Compensation is 
 never so perfect that a little blood does not regurgitate, and as 
 there is necessarily a limit to hypertrophy, so there necessarily 
 arrives a time when further hypertrophy is not possible. The 
 result is that heart failure sets in. There are two periods in 
 the fife history of a diseased heart such as this where digitalis 
 would be useful. The same is true of any valvular lesion, but it 
 is especially true of mitral valve lesions. 
 
 Digitalis is useful during the period of compensation, but it 
 is especially useful after compensation has failed. It is very 
 exceptional to find a case of any valvular lesion where the 
 
 +■ 
 
11 
 
 4- 
 
 compensation is so perfect that it would not be bcnefiteci by 
 digitalis. During the compensation period it should be given 
 only in tonic doses, that is in quantities just sufficient to slightly 
 increase the vigour of the ventricular contractions, but not 
 large enough to slow the pulse. Given in tonic doses it aids 
 the ventricle in better overcoming the ever acting dilating force 
 of the column of blood. It therefore delays the inevitable car- 
 diac failure. 
 
 The other period where digitalis is of use, is when compensa- 
 tion fails — when cardiac failure has set in. The contractile 
 power of the heart is diminished, and when extreme only the 
 upper portion of the ventricle empties itself, just barely enough 
 blood is poured out to sustain life. 
 
 The first effect of heart failure is diminution in the aortic 
 pressure, and this at once shows itself in diminution in the 
 amount of urine excreted. 
 
 When compensation fails h may be restored by the judicious 
 use of digitalis so completely that it will last for several years. 
 
 In cases of aortic incompetency, what we want to produce 
 when compensation fails o'^ is about failing, is sufficient contrac- 
 tion of the ventricle to overcome the dilating powers of the 
 column of blood, and this we can accomplish if the case is not 
 too far advanced. To effect this, however, it is necessary to 
 give the drug in what is called cumulative doses. By this is 
 meant the administration of a second dose before the effects of 
 the first have passed away, and continuing the administration in 
 this way until certain definite effects are brought about. Noth- 
 ing but the greatest good can arise from the use of digitalis in 
 such (juantities, provided its actions are closely watched, and its 
 administration suspended when the symptoms presently to be 
 described make their appearance. 
 
 Many practitioners dread giving digitalis in full medicinal 
 doses. The idea is not uncommon, tliat it may act in an ex- 
 l)losive sort of way and bring about that which it is intended to 
 combat. Now, there is nothing whatever of the mysterious in 
 its actions. When given in a scientific manner its actions can 
 be foretold with a certainty, not excelled by that of any medi- 
 
12 
 
 cinal a<^ent. If there are some practicioners who have a dread 
 of this drug, th'-re are on the other hand others who have not a 
 sufficient fear of it. Any one who has witnessed the reckless way 
 in which it is sometimes given to advanced cardiac cases, must be 
 convinced that not all cases of cardiac diseases die from the 
 effects of their disease, but that some deaths are indirectly, if 
 not directly, due to the too lavish or too long continued use of 
 this agent. The mistakes of the unscientific physician are 
 hidden even from himself in these casos. 
 
 So long as digitalis increases the quantity of urine it is quite 
 safe to proceed with its administration, but when the amount 
 commences raj)idly to diminish then it is a sign that the in- 
 creased blood pressure is giving place to a diminished pressure 
 and that the saturation point has been reached. If in spite of 
 this warning the drug be continued, the quantity of urine will 
 still continue to decrease, until finally it becomes almost com 
 pletcly arrested. The pulse from being slow becomes weak, 
 frequent and irregular, and the heart sounds are reduced to a 
 " toneless tic-tac." When the condition of things just de- 
 scribed has been reached, you can readily understand that a 
 few more doses are all that is necessary to bring the heart to a 
 standstill. 
 
 Digitalis should never be pushed to the extent of quickening 
 the pulse after it has considerably slowed it. A preternatural 
 slowing of the pulse should be as much a warning of saturation 
 as the dimimished quantity of urine. The occurrence of nausea 
 or vomiting after the physiological eflFects are induced should 
 also be taken as a symptom denoting that the safe saturation 
 dose has been reached. 
 
 A diminution in the quantity of urine excreted, an unusual 
 slowing of the pulse and the occurrence of nausea or vomiting, 
 are then the symptoms that indicate that the point has been 
 reached, past which it is not safe to go. Up to the production 
 of these symptoms, nothing but good is obtainable. The first 
 symptom usually of saturation is the slowing of the pulse, and 
 it may be even twenty-four or forty-eight hours after the drug 
 is stopped before its diuretic effects are manifested. It may 
 
 I 
 
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t 
 
 ^ ¥ 
 
 I. 
 
 18 
 
 take four or even five days to bring this about. It is, however, 
 more common t3 find that tlio urine commences to increase in 
 quantity during the third day. The duration of the diuresis 
 depends solely on the dose. 
 
 The changes for the better that are effected by digitalis in per- 
 sons with irretrievably damaged hearts is very striking. The 
 urine from being scanty and high coloured becomes copious and 
 pale. The dropsy disappears. The breathing becomes easier. 
 The pulse from being weak, frequent and irregular becomes 
 strong, slow and regular. These marked results are, however, 
 only obtainable from the use of cumulative doses. 
 
 Now as to the (juantity of digitalis necessary to bring about 
 saturation. You should always remember that different per- 
 sons vary considerably in their susceptibility to its action. 
 Forty minims four times daily for a period of three days wiM, 
 in the majority of cases of heart failure from valvular disease in 
 adults bring about one or more of the saturation symptoms. That 
 is, a quantity slightly short of an ounce of the tincture will, in 
 divided doses, bring about saturation in three days. In excep- 
 tional cases it is necessary to give even larger doses before the 
 desired result is obtainable. One drachm of the tincture four 
 or even six times in the twonty-fonr hours may be necessary. 
 
 Tonic doses should, on the other hand, not exceed twenty 
 minims of the tincture in the twenty-four hours. When these 
 quantities are given the only noticeable effect is a slight in- 
 crease in the vigour of the heart's contractions together with 
 an appreciable rise in the aortic pressure. 
 
 I will now give a brief account of what digitalis did for the 
 man whose heart you have been examining. When he came 
 under observation seven months ago he was suffering from the 
 symptoms of pronounced heart failure. He was d opsical, 
 short of breath and passed but a small quantity of urine. His 
 pulse was very rapid and low in tension. He was troubled with 
 a profuse serous diarrhoea, and his stomach was in a catarrhal 
 condition. Without confinement to bed, twenty minims of the 
 tincture of digitalis four times daily for four days, caused a 
 marked increase in the secretion of urine, with the subsequent 
 
14 
 
 disappearance of the dropsy. He was able to breath much 
 easier. His diarrhoea was arrested and his appetite greatly im- 
 proved. He expressed himself as feeling greatly relieved, and 
 compared to his former distressing condition he was comfortable. 
 He continued in this amended condition for four or five weeks, 
 all the while taking digitalis but only in tonic doses. The ever 
 progressive heart failure even in spite of the support from the 
 digitalis, shewed itself again, but on this oi'casion in a much 
 more pronounced form. As before it was attended by the usual 
 symptoms, but on this occasion they were present in an aggra- 
 vated degree. They indicated such a very serious rupture of 
 the compensation that death appeared to be imminent. Rest 
 in the recumbent position, and the tincture of digitalis in doses 
 of two drachms daily for four days made another marvellous 
 change for the better in his condition. The dropsy again 
 rapidly diminished, but never entirely disappeared. His 
 breathing became much easier and his pulse fuller. So much 
 did he improve that he was once more able to go about. The 
 improvement did not on this occasion last more than two weeks. 
 Once more all the symptoms of advanced cardiac failure made 
 their appearance. He was now removed to the General Hos- 
 pital, where he remained until his death, which occurred a few 
 days after his admission. The immediate cause of death was 
 an " infective" endocarditis. Even ai'ter his admission into the 
 hosjiital he experienced relief from digitalis, ordered him by Dr. 
 Ross, the attending physician. 
 
 I think I have laid before you evidence enough to prove the 
 inestimable value of digitalis in cardiac therapeutics. It is not 
 alone the power it has of prolonging life that should make us 
 prize it highly, but also its marked efficacy in relieving some of 
 the most distressing symptoms that can alflict humanity. The 
 present knowledge that we possess of the actions of digitalis 
 was only acquired by slow degrees. Its scientific application 
 in the treatment of heart failure was not understood until the 
 pharmacology of the drug had been worked out by experiments 
 on the lower animals. If vivisection had done nothing more 
 than give us digitalis, it could be truly said of it that it had 
 
 
 V 
 
 i 
 
•+: 
 
 y 
 
 15 
 
 accomplished a great deal. Wo aro principally indebted for 
 our present knowledge of the actions of this drug to Traube 
 and Schmicdcberg of Germany, G. W. Balfour of Edinburgh, 
 and Lauder Brunton of London. Brunton's and Balfour's names 
 deserve especially to be remembered, the former for the elaborate 
 and painstaking experiments by means of ^vhich he demonstrated 
 its true physiological actions, the latter for showing us how to 
 use it to the best advantage in cases of cardiac failure. 
 
 Mode of Administration. — In prescribing the tincture of 
 digitalis it is as a rule better to give it alone. Its combination 
 with an iron preparation forms not only an unsightly looking 
 mixture, but it is much more apt to disagree with the stomach 
 than when given alone. If, therefore, iron is indicated in a 
 cardiac case, and it frequently is, it is advisable not to combine 
 it with digitalis, but to order it in a separate mixture. 
 
 Powdered digitalis can be prescribed in the pilular form. 
 There is a famous combination known as Baly's pill, which is 
 much relied upon by many physicians to remove a dropsy. The 
 following is the composition of this pill : — 
 
 P? Pulv. Digitalis 
 Pulv. Scillae 
 Pil. Hydrarg aa gr. i. 
 
 S. One pill two or three times daily. 
 
 The use of the so-called active principle, Nativelle's or 
 Qu(5v^enne'sdigitaline,isnot to be recommended when we wish to 
 bring about saturation symptoms, on account of the uncertainty 
 of its action. It, however, can be employed with safety to yjro- 
 duce the tonic etfects of the drug.