Botox was the first mainstream brand of injectables to use the botulinum toxin for cosmetic purposes, even thought it’s been around since the ‘60s. After Botox, the FDA has also approved Dysport and Xeomin, and more brands are awaiting approval.

Even though it seems ubiquitous, the anti-wrinkle cosmetic treatment isn’t as simple as you might think. Discover 10 of the most important things to know about botox, particularly if you’ve never had it before.

1. Your Body Might Reject It

While the purified protein still has neurotoxic properties, botox is only dangerous when ingested or if it makes its way into the bloodstream. However, your body might reject it even if it’s properly injected into your facial muscles. So don’t get too excited before scheduling your appointment since there is a chance that you might be one of the few people who just can’t use it.

2. You Get What You Pay For

While botox isn’t cheap, the price of injections varies widely. One of the most important things you should know about botox is that counterfeit injectables aren’t the only danger. The desired effect depends as much on the skill of the professional who’s injecting it as it does on the quality of the product.

3. You Should Be Completely Open with Your Doctor

Make sure you mention it’s your first time to your doctor. There’s also plenty of other information your should volunteer before the first needle goes in. Be prepared to be honest about your entire medical history, and mention every prescription medication or supplement that you take, no matter how natural it is.

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4. It’s Not Instant

Expecting instant results is a mistake, so one of the big things you should know about botox is that it takes some time to actually settle in. For some people it’s days, for others it can take around a week. So don’t schedule injections less than 2 weeks before any big event.

5. Side Effects May Vary

For most patients, side effects can include bleeding, bruising, swelling, and redness, that usually last for very little. The intensity of these symptoms is also up to the skills of the licensed professional who’s injecting you. You might also have to deal with a headache in the first 24 hours after the treatment.

6. It Can Make You Look “Frozen”

When you’re getting a dose that’s too big, your muscles can end up being paralyzed a bit too much. You can also end up with a droopy brow or eyelid. One of the most important things you should know about botox is that you can’t just go back for more or for a different treatment to fix the issue. If something went wrong, you just have to wait it out.

7. You Can’t Take a Nap After the Treatment

Whether you’re using Botox, Dysport or Xeomin, you have to let it settle in your muscles for a few hours after getting the injections. Staying upright is important for at least 4 hours after the treatment. You don’t have to actually stand up, you can be in a seated position, but make sure you don’t lie down or slide in your chair.

8. It’s Only FDA Approved for Your Eye Area

One of the most important things you should know about botox is that injectable with the botulinum toxin are only FDA approved for crow’s feet and frown lines in between your brows. Most licensed professionals will inject it in other areas as well, from forehead lines to neck lines, but there’s a bit more risk involved.

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9. Blood Thinning and Botox Don’t Mix

Taking any medication or supplements with blood thinning effects can increase the bleeding and bruising side effects. You shouldn’t be taking any blood thinners for at least a week before your appointment. These include everything from aspirin and ibuprofen (Advil) to fish oil, vitamin E, ginseng, and ginkgo biloba.

10. You Have Plenty of Restrictions After Botox

Since you want the toxin to stay put in your facial muscles, one of the things you should know about botox is that you should definitely avoid strenuous physical activity in the first 24 hours after the injections. You should also avoid touching, rubbing, massaging the skin in the treated area, which also means microdermabrasion, chemical peels or even facials should be avoided.