What will be a harmful side effect of a cold medicine

Some harmful side effects of cold medicine can include drowsiness, dizziness, blurred vision, dry mouth, nausea, vomiting, and constipation. Additionally, some cold medicines can interact negatively with other medications, leading to potential complications. Overuse of cold medicine can also lead to dependence and drug resistance. It is important to read the labels carefully and adhere to recommended dosages to avoid these harmful side effects.