Is taking a lot of laxatives dangerous?

Yes! Laxatives should only be taken under doctor supervision. Some directly irritate your colon to contract to remove stool and can lead to depending on them for a bowel movement. Others work by removing water from your body & put it into your colon to "flush" the stool out. Both can lead to dehydration and electrolyte imbalance if taken improperly. See your dr if you are having constipation.
Oh yes... Before you contemplate long term laxative dependency, seek medical evaluation--rule out metabolic causes of constipation (e.g. Low thyroid or adrenal conditions), distinguish slow versus normal transit constipation, consider a primary rectal dysfunction that may be treatable with biofeedback, check for structural pathology or extrinsic impingement, or intermittent ileus (e.g. Pseudo-obstruction).