Side effects of Remdesivir by Mayo:
More common

Back pain
chest tightness
chills
cough
dark-colored urine
difficulty swallowing
fast heartbeat
fever
flushing
headache
hives, itching
light-colored stools
nausea and vomiting
puffiness or swelling of the eyelids or around the eyes, face, lips, or tongue
stomach pain, continuing
trouble breathing
unusual tiredness or weakness
yellow eyes or skin

Less common

Seizures
skin rash
Long term side effects:
More common

Bleeding, blistering, burning, coldness, discoloration of skin, feeling of pressure, hives, infection, inflammation, itching, lumps, numbness, pain, rash, redness, scarring, soreness, stinging, swelling, tenderness, tingling, ulceration, or warmth at the injection site

Other side effects not listed may also occur in some patients. If you notice any other effects, check with your healthcare professional.