Hyaluronidase is a genetically designed protein.

Hyaluronidase is used together with fluids injected into the body to treat dehydration. Hyaluronidase can also be used as an aid in helping your body absorb other injected medications.

Hyaluronidase is also used to help contrast dyes in your body show more clearly on certain types of x-rays or scans.

Hyaluronidase may also be used for purposes not listed in this medication guide.

Serious drug interactions can occur when certain medicines are used together with hyaluronidase. Tell your doctor about all your current medicines.

Hyaluronidase is injected under the skin, into a muscle, or into other tissues of the body.

A healthcare provider will give you this injection.

Hyaluronidase should not be injected into a vein (as an intravenous injection).

You should not be treated with hyaluronidase if you are allergic to it.

Your doctor may perform a skin test to see if you are allergic to hyaluronidase before you receive the medication.

Some medicines can cause unwanted or dangerous effects when used with hyaluronidase. Your doctor may change your treatment plan if you also use:

• furosemide (Lasix);

• phenytoin (Dilantin);

• a sedative or anxiety medication (such as diazepam, lorazepam, alprazolam, Valium, Xanax, Ativan, Tranxene, and others);

• aspirin or salicylates;

• cortisone or ACTH (Corticotropin);

• estrogens; or

• an antihistamine (such as a cold or allergy medicine).

Tell your doctor if you are pregnant.

It may not be safe to breast-feed while using this medicine. Ask your doctor about any risk.

Because you will receive hyaluronidase in a clinical setting, you are not likely to miss a dose.

Seek emergency medical attention or call the Poison Help line at 1-800-222-1222.

Follow your doctor's instructions about any restrictions on food, beverages, or activity.

Get emergency medical help if you have signs of an allergic reaction: hives; difficulty breathing; swelling of your face, lips, tongue, or throat.

Hylenex may cause serious side effects. Call your doctor at once if you have:

• swelling in your hands, feet, or other body areas; or

• pain, swelling, itching, or redness where the injection was given.

This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

Other drugs may affect hyaluronidase, including prescription and over-the-counter medicines, vitamins, and herbal products. Tell your doctor about all your current medicines and any medicine you start or stop using.