Thanks for your query.
It is common to get itch and inflammation after any insect bite, afterwards your skin may show pigmentation or dark spot. Frequent scratching can result in further inflammation or infection so try to avoid it to prevent further damage.Some insect bites
can cause skin allergies and irritations.
You can use over the counter gels to reduce inflammation and irritation. Disinfectants and ointments
for sever itching can be used.
Oil can be applied over inflamed area.
Rub the flesh of tomato, lemon, or papaya on the bite marks twice a day until the dark spots disappear.
For prevention always use an insect repellent when you are at risk of insect bite.
Hope it helps.