Quantifying the short term effect of Stalevo on me
The attached graph shows the pharmacodynamics of a single (75 mg levodopa) Stalevo pill on me.
dynamics.png
Side-to-side tap test results (high is good):
Baseline (4 readings).
Mean left = 13.03 taps, right = 11.84 taps
After taking the pill (17 readings)
Mean left = 21.34, right = 18.36
Max left = 29.24, right = 24.23
First minor effect seen 30 minutes after swallowing the pill.
First major effect seen after 50 minutes.
Peak reached after 90 minutes.
Back to baseline results after 165 minutes.
Correlation left/right = 0.966
The area under the curve and above the baseline (gives a measure of the drug's total effect) = 2438 taps.
Details.
To reduce the effect of my previous drug intake on the result, I started this experiment "off". This is difficult for me because I take some long acting medication, Requip XL and rasagiline. I was off these for 36 hours before starting. I was also off my fast acting medication, Stalevo, for 14 hours. This meant that, although not all the drugs had been washed out of my system, whatever was left was unlikely to have a large confounding effect on the result. Meals can also affect the results: I ate a large meal 7 hours before starting and ate half a slice of bread with the pill. I drunk some water on several occassions. Similarly, exercise can also affect the result, I was at my desk for almost the whole 3 hours 35 minutes that I ran the test.
To measure the results I used my online, side-to-side tap test program:
http://www.parkinsonsmeasurement.org...eToSideTap.htm
This measures the number of times you can type q followed by p in 30 seconds using just the index finger of one hand. It is done separately for each hand. I took 21 readings, one every 10 minutes, except there was 15 minutes between my last reading before taking the pill and my first reading after taking the pill and 15 minutes between each of the last three readings.
In the table below times are in minutes. Negative times represent the period before the drug was taken. LH and RH denote the left and right hand, respectively. Taps refers to the number of q,p cycles done in 30 seconds using just the index finger of one hand.
Time,LH_Taps,RH_Taps
-35,13.37,11.48
-25,12.81,11.81
-15,12.95,11.94
-5,12.98,12.11
10,12.92,12.85
20,13.85,11.41
30,15.98,12.53
40,15.05,12.41
50,18.42,17.55
60,26.43,21.55
70,27.41,21.87
80,25.53,22.84
90,29.24,24.23
100,28.23,24.18
110,26.75,24.08
120,26.08,21.97
130,23.60,21.81
140,22.32,17.17
150,17.38,17.10
165,12.17,9.34
180,13.02,10.12
John