Despina Stamatopoulous is a 65-year-old widow with congestive cardiac failure. She is taking the ACE inhibitor enalapril for her cardiac failure and the penicillin ampicillin for a respiratory...

Despina Stamatopoulous is a 65-year-old widow with congestive cardiac failure. She is taking the ACE inhibitor enalapril for her cardiac failure and the penicillin ampicillin for a respiratory infection. How would her condition affect the excretion of ampicillin? Why should a person on a non-selective MAO inhibitor avoid preparations such as nasal decongestants for the common cold?