An article in this week's issue of the British Medical Journal warns that, despite having relatively few side effects, the long-term consequences of botulinum toxin, a potent neurotoxin otherwise known as Botox, are still unknown. Botox has gained popularity in recent years because of its effectiveness on facial lines and wrinkles. Since 1998, the toxin's use for dermatology conditions has risen by 1500 percent with sales increasing from $25 million in 1993 to over $300 million in 2001.