Welcome to HealthcareMagic. This redness and formation of lumps under the skin after methionine
injection could be due to injection local trauma leading to a hematoma
formation or a side effect of this drug if you have taken this drug for the first time. Apply warm compresses and take some anti inflammatory pain killers like Ibuprufen or Diclofenac
. If the symptoms are severe or if there is intense itching then allergic reaction
can be a cause and you need antihistaminics and steroids for this. Consult a doctor in this case.
Hope it helps. Regards.