Label the 20 pills A through T in order of their appearance in the diagram:
The clues can be rewritten as these equations:28=B+C+D
From 43=H+I+J+K and 21=I+J we know 22=H+K
From 28=B+C+D and 33=B+D+E we know E - C = 5
From 22=F+G+H and 26=F+H+I we know I - G = 4
From these last two results and 22=C+G+Q and 32=E+I+O we know 27=E+G+Q, 28=E+G+O, O - Q = 1
Also, from 37 = C+G+J+N and I - G = 4 and I + J = 21, we have C + N = 20
From 47=A+E+O+R, 35=B+K+M, 22=C+G+Q, 18=D+K+P, 40=F+L+N+T, 43=H+I+J+K, we know 205 = A+B+C+D+E+F+G+H+I+J+K+K+K+L+M+N+O+P+Q+R+T which yields 5 = S - 2K, or 2H+S=49.
Use these expressions to eliminate E, I, O, S, H, J, and N from the rest of the equations:28=B+C+D
Then the following expressions can be arrived at successively with substitution after each step:34=P+Q+R+2K - (24=M+P+Q-C) + 35=B+K+M - (28=B+C+D) + 18=D+K+P - (34=P+Q+R+2K) => 1 = 2K-Q
This lets everything be written in terms of K:E = C + 5 = 43 - 5K
From T = 32 - K it is known that K is no more than 7, and from A = 34 - 2K, K is at least 7. Then:A = 20
The center column contains AEHLORT, which translates to 20 8 15 18 14 5 4 by this solution, or (by index into the alphabet), THORNED.