Company Profile. Integra LifeSciences, a world leader in medical technology, is dedicated to limiting uncertainty for surgeons, so they can concentrate on providing the best patient care. Integra offers innovative solutions in orthopedic extremity surgery, neurosurgery, and reconstructive and general surgery.
There are subtle differences in how long the drug works and how quickly it works. Levitra works a little longer than Viagra. They both take effect in about 30 minutes. With Levitra, the effects last for about 5 hours. With Viagra, the effects last approximately 4 hours. Cialis works a bit faster (within about 15 minutes), and the effects last much longer -- up to 36 hours in some cases. Stendra can start working in as little as 15 minutes and last up to 6 hours.
It can take up to six weeks after the first dose of medication before it has an antidepressant effect. For some people it can take up to eight weeks or a little longer before they start to feel better, and the maximum benefit is felt after six months.