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Botox-Type Drugs Can Treat Many Eye Conditions

— A good approach when muscular dysfunction is the cause, expert says

MedpageToday

ANAHEIM, Calif. -- Botox and its wrinkle-fixing sibling drugs have gained a foothold as treatments for conditions as varied as headaches and incontinence. This week, an ophthalmologist told an audience of optometrists that the medications can also treat an impressively long list of ophthalmic conditions, even severe ones that may leave patients virtually blind.

"This is really where you can change people's lives in regards to some of the problems they have, especially the dystonias, these involuntary sustained repetitive muscle contractions. They can be very devastating," said , an ophthalmologist with the Mayo Clinic Health System in Albert Lea, Minn. He spoke during a presentation at the .

According to Skorin, botulinum toxins can effectively treat dystonias such as benign essential blepharospasm (BEB), which causes eyelid spasms. "I see this the most in my practice. These people are blinking constantly," said Skorin, who spoke of a patient who had to hold up his eyelids to drive to the doctor's office. "These people can become functionally blind: They can't keep their eyes open enough to drive, read, watch television."

In terms of treatment, it's important to remember that the drugs are designed to be injected into muscles, he said. "Let's say somebody has BEB, and they also have wrinkles," he said. "The injection for cosmetic purposes or the dystonia is exactly the same. You'll never inject in a crease or furrow. You want to inject in muscles themselves."

Another use: The treatment of post-Bell's palsy and the related "crocodile tears" form of synkinesis: "They'll start getting teary every time they chew, or even if they think of food and start salivating. You can do Botox injections directly into lachrymal gland. It works very well."

Other conditions for which botulinum toxin agents can be used include hemifacial spasm, apraxia of lid opening, segmental cranial dystonia, idiopathic oromandibular dystonia (Breughel syndrome), and idiopathic orofacial dystonia (Meige syndrome), said Skorin.

They can also be used to treat strabismus ("you inject the overreacting muscle to weaken it so the eye straightens itself out"), eyelid retraction and spastic entropion, he said.

Skorin offered these tips about the use of botulinum toxins for ophthalmologic conditions:

  1. Understand the various Botox-type medications. Botox is no longer the only Type A botulinum toxin on the market, Skorin said. Alternatives include Xeomin, which is unique because it is a "naked injectable" that doesn't require additives, and Dysport. Myobloc, a Type B formulation, is also available.
  2. Keep contraindications in mind. The drugs are not recommended for patients with inflammation or infection, pregnancy or lactation. And while Skorin said he's used the drugs in ALS and myasthenia gravis, "you should be very cautious about using a neuromuscular weakening agent in anyone with a neuromuscular disease."
  3. Beware of the development of antibodies. About 3%-5% of patients will develop them, eventually making the drugs ineffective.

Warning signs include more frequent visits -- "a person's been getting injections every 3 months, and they start coming in 2 weeks earlier, a month earlier" -- or a need for higher and higher doses, he said.

What to do? "You don't want to fall into the trap of 'Come in sooner, and we'll give it to you.' You'll help them build antibodies quicker by giving injections more often," he said. In addition, insurers won't cover injections more frequently than every 3 months, he said.

Instead, he increases doses until he's forced to try another botulinum toxin.

"I want to peter out with the particular agent before I switch to a different agent," he said. "If they develop antibodies for all agents, they're out of luck. The botulinum toxin will never work on them again. Luckily, that's very rare."

  • author['full_name']

    Randy Dotinga is a freelance medical and science journalist based in San Diego.

Primary Source

American Academy of Optometry

Skorin L "Ophthalmic and neurologic uses of botulinum toxin" AAOPT 2016.