- Intake of prohibited concomitant medication such as midodrine, intake of medication associated with vasodilatation or induction of liver enzymes; neuroleptics; certain drugs known to be substantially metabolized through the following cytochrome P450 isoenzymes: 1A2, 2B6, 2C19, 2C9, 2D6 and 2E1; or any other drug for the treatment of orthostatic hypotension (including off-label use), such as non-steroidal anti-inflammatory drugs, beta blockers, somatostatin