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Generic name:  collagenase clostridium histolyticum-aaes (for injection)
Drug class: Miscellaneous uncategorized agents

Medically reviewed by Judith Stewart, BPharm. Last updated on Jun 27, 2022.

What is Qwo?

Qwo is a prescription medicine used for the treatment of moderate to severe cellulite in the buttocks of adult women.
It is not known if this medicine is safe and effective in children.

Who should not receive Qwo?

You should not receive Qwo if you:

  • Are allergic to any collagenase or to any of the ingredients. See the end of this page for a complete list of ingredients.
  • Have an active infection in the treatment area.

Before receiving Qwo

Before receiving Qwo, tell your healthcare provider about all of your medical conditions, including if you:

  • have had an allergic reaction to a Qwo injection in the past
  • have a bleeding problem
  • are pregnant or plan to become pregnant. It is not known if this medicine will harm your unborn baby.
  • are breastfeeding or plan to breastfeed. It is not known if this medicine passes into your breast milk. Talk to your healthcare provider about the best way to feed your baby if you receive Qwo.

Tell your healthcare provider about all the medicines you take, including prescription and over-the-counter medicines, vitamins, and herbal supplements. Especially tell your healthcare provider if you take a medicine that prevents the clotting of your blood (antiplatelet or anticoagulant medicine).

How will I receive Qwo?

  • Qwo is injected into the fat (subcutaneously) of each single buttock (treatment area) by your healthcare provider. You may receive up to 12 injections per treatment area.
  • Each treatment visit may include up to 2 treatment areas.
  • Qwo injections will be given 21 days apart for 3 treatment visits.

Qwo side effects

Qwo may cause serious side effects, including:

  • Allergic (hypersensitivity) reactions, including anaphylaxis. Call your healthcare provider right away if you have any of these symptoms of an allergic reaction after an injection of Qwo:
    • hives
    • trouble breathing
    • low blood pressure
    • swollen face
    • chest pain
    • dizziness or fainting
  • Injection site bruising.

The most common side effects include bruising, pain, areas of hardness, itching, redness, discoloration, swelling and warmth in the treatment area.
These are not all of the possible side effects. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA 1088.

General information about Qwo

Medicines are sometimes prescribed for purposes other than those listed in a Patient Information leaflet. If you would like more information, talk to your healthcare provider. You can ask your pharmacist or healthcare provider for information that is written for health professionals.

What are the ingredients in Qwo?

Active ingredient: collagenase clostridium histolyticum
Inactive ingredients: mannitol, sucrose, tromethamine, and hydrochloric acid
The diluent contains: calcium chloride dihydrate, sodium chloride, and Water for Injection, USP

Popular FAQ

How many times can you do QWO?

QWO is usually given initially as three separate treatment sessions, each spaced approximately 21 days apart, for optimal results. During each treatment session, a woman may receive up to 12 QWO injections per buttock. These will be administered into the dimples of each butt cheek, for a maximum total 24 injections (12 each buttock) per session. After the third session, you should wait four weeks before fully evaluating the results. Depending on your results, and the extent of your cellulite, you may need further treatment sessions. Treatment lasts at least a year, after which treatment may be repeated if necessary.

How long does QWO cellulite treatment last?

You can expect your QWO treatment to last at least one to two years, likely much longer, and for some women QWO treatment is permanent.

How does QWO work on cellulite?

QWO is a mixture of two highly specific bacterial collagenases, AUXI and AUXII, which are enzymes that have been shown in a laboratory to break down the structure of collagen type 1 and 3 in fibrous septae (in women, these are crisscrossed fibrous structures made of collagen that connect the dermis to the fascia) to release the cellulite dimple. When QWO is injected to treat moderate to severe cellulite, the exact way it works is unknown, but it is believed to initiate a process called enzymatic subcision and remodeling (also called ESR). During ESR, fat globules begin to reorganize and spread more evenly with the breakdown of the fibrous septae. ESR also stimulates the formation of new collagen, and the collagen support network rebuilds itself into thinner, smaller, fibrous septae. This thinner network reduces tension and helps thicken the dermis, creating a smoother appearance.

At recommended dosages, QWO does not damage arteries, nerves, or large veins because these contain type 4 collagen. Small blood vessels may leak because their support is affected by QWO and it is the leaking of these small blood vessels that causes the appearance of bruising.

Can I workout after QWO?

It is best not to workout, do strenuous physical activity, or engage in heavy exercise for 24 to 48 hours after QWO treatment. This allows the treatment time to settle into the areas where it has been injected and take effect and minimizes its movement and spread – if the product spreads out too much you may experience a decreased effect. In addition, there is usually some soreness and pain within the first 48 hours, and you probably won’t feel like working out.

Can you sit after QWO treatment?

Yes, you can sit after QWO treatment, but many people describe soreness after sitting for long periods, or when going from a seated to a standing position. Pain after QWO treatment is often described as like having gone through a very intense lower-body workout. The pain and soreness come on within about 12 to 14 hours but tend to subside in about 48 hours. It is best to plan some downtime after having the injections to give your body time to recover.

Do QWO injections hurt?

QWO injections are relatively painless, and most people report the injection hurts less than Botox, although some people may feel a slight pinch as the injection goes in. Icing the area beforehand and pinching the skin up before inserting the needle reportedly makes it hurt less. You do not need anesthesia with a QWO injection

Bruising after QWO is common, affecting up to 84% of women, and usually lasts up to 2 to 4 weeks. The first treatment of QWO usually causes the most significant bruising but subsequent treatments tend to cause less bruising. Continue reading

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Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.