Melphalan affects everyone differently, but it does tend to more commonly affect the GI tract of patients who receive it. Quite often patients experience nausea, vomiting, and/or diarrhea as a side effect of the chemotherapy. Talk to your doctor about preventative or reactionary medications that can help with this. 

• Chemotherapy may alter taste and cause food to have a metallic flavor. Eat small, frequent meals and stick to foods that appeal to you.
• Avoid spicy, fatty, fried, and sugary foods. Medications can help, but if you can’t keep anything down for 24 hours, notify your nurse.
• Stay hydrated, limit caffeine, eat small frequent meals, and consult your nurse before taking over-the-counter medication.

You can also check out patient sources solutions to these side effects here: 

Check Solutions for GI Issues

Remember to talk to your doctor before implementing any medically-based solutions or supplements or making large lifestyle changes.