The article you refer to is written by mainstream medicine. It contains information from doctors and pharmaceutical representatives.
Although I realize that some coming into this forum may be taking prescription medicines, and may be under a doctor's care, the purpose of this forum is to educate the public on natural healing and natural supplements.
The purpose of this forum is to show people how they can reach optimum health by using natural products, what God put on this earth, not a bunch of synthetic drugs. Synthetic drugs are not natural. Whenever I recommend a herb I always caution that anyone taking any type of a prescription drug must consult with their physician or pharmacist to ascertain the possible interactions, not because of the danger of the herbs, but rather because of the danger caused by the synthetic medicines prescribed by doctors.
The article that you referred to is absolutely false and full of misinformation. Curious that the very people that are on a campaign to rid humanity of herbs, vitamins and a healthy lifestyle are the very ones that have written this article.
I will take the side effects you have listed one by one:
First of all, as with any drug prescribed by a physician, if anybody has an unpleasant side effect, they should immediately stop taking the supplement, whether it be black cohosh or anything else.
"Black cohosh can depress heart rate, anyone with any type of heart disease should not use this herb."
This can happen if taken in conjunction with prescription drugs that do not agree with it or if taken in extreme amounts. In no credible site did I find that anybody with heart disease should not use this herb. However, If one suspects they have heart disease or any other serious illness, they should check with their physician or pharmacist.
"Other possible side effects include dizziness, diarrhea, nausea, headaches, shakes, low pulse, vomiting."
Again, one may suffer from these side effects if they take Black Cohosh in conjunction with a prescription drug that it does not agree with or if taken in large amounts.
Black Cohosh should not be taken if pregnant, lactating, and/or breastfeeding.
Below is an article on Black Cohosh from Dr. Mercola's site. Please be sure to read his personal comments.