Many prescription and nonprescription medicines can cause swelling. You may be having an allergic reaction if swelling develops suddenly after taking a new medicine. The seriousness of the allergic reaction caused by a medicine will vary. If you think that you are having an allergic reaction to a medicine, call your health professional to discuss your symptoms.

Medicines or solutions used in medical procedures that may cause swelling related to an allergic reaction include:

• Antibiotics, such as penicillins, cephalosporins, or sulfa (sulfonamides).
• Aspirin as well as other nonsteroidal anti-inflammatory drugs (NSAIDs).
• Vaccines.
• Antiseizure medicines.
• Barbiturates.
• Local anesthetics.
• Contrast dyes used in X-ray studies.
• Blood products.
• Certain enzymes, such as trypsin.

Medicines that may cause swelling as a side effect include:

• Hormones, such as estrogen and progesterone oral contraceptives or testosterone.
• Dilantin, which causes swelling of the gums (gingival hypoplasia).
• Corticosteroid therapy, such as prednisone or dexamethasone, when taken for long periods of time.
• ACE inhibitors, such as captopril or quinapril.

Call the health professional who prescribed the medicine to determine whether you should stop taking it or take a different one. An appointment may not be necessary. If you are taking a nonprescription medicine, stop taking it. Call your health professional if you feel you need to continue taking it.