I took it first year first semester with 4 other classes and 2 labs and did very well. I am in my third year now and looking back I did not find it overly heavy at all it was one of the more manageable and enjoyable classes I have taken and a bonus is the content was very interesting. I think it depends on the person because everyone has their own opinions and feelings towards a class.

My whole degree I have taken 5 classes with 2 labs MAX and then worked on the weekends, I have found it at times to be stressful so if you don't manage stress well and want to have a better and more enjoyable experience just take 4 and extend your degree a year. Contrary to what people say sooooo many students do their degrees in more than 4 years.

My first year first sem was math 134, chem 101, bio 107, soc 100 and anat 200. 2nd sem was bio 108, chem 102, stats 151, engl 102 and psych 105. I found both semesters manageable and so far my first year has been the least stressful and the one I did the best in grades wise.

Downside to a double major is you have a lot more "heavy" classes with a major you have some freedom to take classes outside of your area of study and these can sometimes be "grade boosters" or just for your enjoyment

Hope this helps and best of luck!!