Take a lower dose. Test your product.
MDMA's appetite suppression shouldn't last that long from my experience.
Invest in some protein shakes, fruit juice, multi-vitamins and force those liquid calories down.
Moving on...
Marijuana is safer than other alternatives, but does not always work with everyone.
Otherwise, there are plenty of drugs that offset the appetite effects of CNS stimulants.
Benzodiazepines in small quantities are a good choice.
GHB, used without other depressants(Deadly);with someone trustworthy and experienced can also help.
Alcohol does no justice for your body's current deprived health and severely increases risks.
But using a drug to off-set negative side effects of another drug is a bad road to run down.