If you develop a severe sunburn or skin irritation, contact your doctor. Some people have developed dry mouth, dizziness, constipation, or confusion while taking St. John's wort, but few have had to stop taking the drug because of side effects. When you take St. John's wort with prescription medicines it may increase or decrease the effects of the medicines. Or the combination may cause harmful side effects. Talk to your doctor if you are taking birth control pills.
Some natural remedies have the same effects as prescription medicines.
This means there is a danger of being overmedicated. If you have any unusual effects while taking any natural remedy, get advice from a doctor right away. Natural remedies and prescription medicines may interact. Lack of standardization may result in products with different strengths and effects. Lack of quality control may allow contamination of products.