Most of south america has a population density of people per square kilometer.

The map below shows how Population density (people per sq. km of land area) varies by country in South America. The population density of 65.97 people per square kilometers. Current population estimates for developing countries that lack recent census data and pre- and post-census estimates for countries with census data are provided by the United Nations Population Division and other agencies.

answer; delirium is a common adverse reaction seen when elderly patients take diphenhydramine;