Botox injection a drug preparation marketed by Allergan Inc worldwide including in India is found to be beneficial for patients suffering from chronic headache and migraine pain in clinical studies being conducted in the US.

The phase II trials to check the efficacy of the drug among migraine patients has been completed and the phase III trials are going on now, according to the company officials. Once the trials are completed successfully, the company may go for approval for marketing the drug for new indication.

Botox is approved for conditions like Blepharospasm, Cervical Dystonia, severe Primary Axillary Hyperhidrosis that is inadequately managed with topical agents and strabismus. It is also used for certain cosmetic purposes.

Botox is the brand name of a toxin produced by the bacterium clostridium botulinum. In large amounts, this toxin can cause botulism. Despite the fact that one of the most serious complications of botulism is paralysis, scientists have discovered a way to use it to human advantage. Small, diluted amounts can be directly injected into specific muscles causing controlled weakening of the muscles.

The FDA approved such usage in the late 1980s upon the discovery that Botox could stop ailments like blepharospasm (uncontrolled blinking) and strabismus (lazy eye). Cosmetic physicians have been using Botox for years to successfully treat wrinkles and facial creases. In April 2002, Botox gained FDA approval for treatment of moderate-to-severe frown lines between the eyebrows - called glabellar lines. However, Botox is often used for other areas of the face as well.

According to informed sources, several doctors for treating severe headaches and migraine pain are prescribing the product. The Drug Controller General of India (DCGI) does not approve the drug for the purpose in India.

When contacted, sources in Allergen admitted that the company is aware of such off label uses of Botox by the medical profession in the country. An eminent ENT hospital commenting on the issue, said that the drug was used only for treatment of the larynx and he is not aware about its efficacy in the treatment of chronic headaches.