Notify me of follow-up comments by email. Notify me of new posts by email. Reality Read more…. You start to think about possible digoxin toxicity…. Premature ventricular contractions PVCs. Digoxin-specific antibody. The following two tabs change content below. Bio Latest Posts. Patients taking digoxin are carefully monitored and a number of antidotes have been developed to treat overdoses.
The problem, as with all drugs, is side-effects. It is therefore the interaction between the drug and the enzymes located elsewhere in the body that is the cause of side-effects. These are the cells that give us our colour perception. It is very rare, but some people taking digoxin and related drugs can experience haziness to their vision, or a yellow tinge to everything they see, known as xanthopsia.
Occasionally, points of light may appear to have coloured halos around them. Rarer still are effects on pupil size, such as dilation, constriction or even unequal-sized pupils. More circumstantial evidence comes from the two portraits Van Gogh produced of his doctor, Paul Gachet, showing him holding a foxglove flower. All of this is very interesting but it is pure speculation. These five animals were anorexic on the day after dosing. Subsequently, no treatment-related findings were observed in any animals until the end of the study period i.
Typical waveforms of the standard full-field ERGs at baseline and those recorded after digoxin dosing are shown in Figure 1. The amplitude and implicit time of the ERG components are summarized in Table 1. The rod response was enhanced and delayed: significant increases in the amplitude and implicit time of the b-wave after dosing were detected.
The combined rod—cone response also was delayed: the implicit time of the a- and b-waves significantly increased after dosing. The single-flash cone response and the Hz flicker were delayed and attenuated: significant increases in the b-wave implicit time after dosing were detected.
Five out of six animals showed obviously decreased b-wave amplitude after dosing in both the single-flash cone response and the Hz flicker, although a statistically significant difference was not detected.
The changes in the standard full-field ERGs mentioned above were most prominent at 24 hours after dosing. These changes gradually but fully recovered within 28 days after dosing. Figure 1. View Original Download Slide. Typical waveforms of the standard full-field ERGs in a digoxin-treated monkey. Digoxin at a dose of 0. Arrowheads indicate onset of the light flashes. The responses at baseline gray trace are superimposed on those obtained after dosing of digoxin black trace. Each trace represents an average of 3 to 10 responses.
Figure 1 Typical waveforms of the standard full-field ERGs in a digoxin-treated monkey. Table 1. View Table. Typical waveforms of the dark-adapted response to flashes of increasing intensity in vehicle- and digoxin-treated monkeys are shown in Figure 2 , and intensity-response functions of the dark-adapted response in vehicle- and digoxin-treated monkeys are shown in Figure 3.
Digoxin enhanced and delayed the b-wave. In the digoxin-treated group, the amplitude and implicit time of the b-wave were significantly increased in comparison with both the vehicle-control values and the predosing values: no interaction was detected between these changes and stimulus intensity.
Figure 2. Typical waveforms of the dark-adapted response to flashes of increasing intensity in vehicle- and digoxin-treated monkeys.
Vehicle or digoxin at a dose of 0. The responses obtained before dosing gray trace are superimposed on those obtained 24 hours after dosing black trace in the right panels. Each trace represents an average of three responses. Figure 2 Typical waveforms of the dark-adapted response to flashes of increasing intensity in vehicle- and digoxin-treated monkeys.
Figure 3. Intensity-response functions of the dark-adapted response in vehicle- and digoxin-treated monkeys.
The dark-adapted response to flashes of increasing intensity were recorded before open circles and after closed circles dosing, and the amplitude of the a- and b-waves A and the implicit time of the b-wave B were measured as described in the text. Figure 3 Intensity-response functions of the dark-adapted response in vehicle- and digoxin-treated monkeys.
Typical waveforms of the light-adapted response to flashes of increasing intensity in vehicle- and digoxin-treated monkeys are shown in Figure 4 , and intensity-response functions of the light-adapted response in vehicle- and digoxin-treated monkeys are shown in Figure 5.
Digoxin remarkably attenuated the a-wave. In the digoxin-treated group, the a-wave amplitude was significantly decreased in comparison with both the vehicle-control values and the predosing values. The interaction between response and stimulus intensity of the a-wave amplitude in the digoxin-treated group was significant: the attenuated a-wave compared with the predosing values was detected only at high stimulus intensities.
The b-wave amplitude before dosing in the digoxin-treated group was significantly higher than that in the vehicle-treated group. The b-wave amplitude after dosing in the digoxin- and vehicle-treated groups did not differ, since the b-wave amplitude significantly decreased in the digoxin-treated group after dosing. The interaction between response and stimulus intensity of the b-wave amplitude in the digoxin-treated group was significant: significant attenuation in the b-wave was detected only at middle stimulus intensities.
The implicit time of the b-wave in the digoxin-treated group was significantly increased after dosing in comparison with both the vehicle-control values and the predosing values: no interactions were detected between these changes and stimulus intensity.
Figure 4. Typical waveforms of the light-adapted response to flashes of increasing intensity in vehicle- and digoxin-treated monkeys. Each trace represents an average of 10 responses. Figure 4 Typical waveforms of the light-adapted response to flashes of increasing intensity in vehicle- and digoxin-treated monkeys.
Figure 5. Intensity-response functions of the light-adapted response in vehicle- and digoxin-treated monkeys. The light-adapted response to flashes of increasing intensity were recorded before open circles and after closed circles dosing, and the amplitude of the a- and b-waves A and the implicit time of the b-wave B were measured as described in the text. Figure 5 Intensity-response functions of the light-adapted response in vehicle- and digoxin-treated monkeys.
Typical waveforms of the rod a-wave and the cone a-wave in vehicle- and digoxin-treated monkeys are shown in Figures 6 and 7 , respectively. Model parameters of the a-wave analysis are summarized in Figure 8 and Table 2.
In the rod a-wave, no marked changes were found in the waveform or in the model parameters. In the cone a-wave, the R max in the digoxin-treated group was significantly reduced in comparison with both the vehicle-control values and the predosing values; the mean R max after dosing in the digoxin-treated group was lower than that in the vehicle-treated group by 0.
On the other hand, no change was detected in the S. Figure 6. Typical waveforms of the rod a-wave in vehicle- and digoxin-treated monkeys. The dotted lines signify the curves fit from Equation 1 in the text. Figure 6 Typical waveforms of the rod a-wave in vehicle- and digoxin-treated monkeys. Figure 7. Typical waveforms of the cone a-wave in vehicle- and digoxin-treated monkeys. The dotted lines signify the curves fit from Equation 2 in the text.
Each trace represents an average of six responses. Figure 7 Typical waveforms of the cone a-wave in vehicle- and digoxin-treated monkeys. Figure 8. The effect of digoxin on the a-wave in monkeys.
Figure 8 The effect of digoxin on the a-wave in monkeys. Table 2. Electroretinogram parameters are summarized in Table 2. In the digoxin-treated group, the implicit time of the b-wave was significantly increased in comparison with both the vehicle-control values and the predosing values. Meanwhile in the d-wave implicit time, significant increase compared with the predosing values was detected in the digoxin-treated group. Oxford: Oxford University Press; It could have happened to Van Gogh: a case of fatal purple foxglove poisoning and review of the literature.
Eur J Emerg Med. Hammacher, Abraham M. Vincent van Gogh: Genius and Disaster. Harry N. Abradale Press, New York. New York, NY: Abrams; Sweetman, David. Crown Publishers, New York. Download references. You can also search for this author in PubMed Google Scholar. Reprints and Permissions. Demir, D. Van gogh and the obsession of yellow: style or side effect.
Eye 33, — Download citation. Received : 14 January Revised : 19 July
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