Get emergency medical help if you have signs of an allergic reaction to NovoLog: redness or swelling where an injection was given, itchy skin rash over the entire body, trouble breathing, fast heartbeats, feeling like you might pass out, or swelling in your tongue or throat.
Call your doctor at once if you have:
heart problems - swelling, rapid weight gain, feeling short of breath; or
low potassium - leg cramps, constipation, irregular heartbeats, fluttering in your chest, increased thirst or urination, numbness or tingling, muscle weakness or limp feeling.
Common NovoLog side effects may include:
low blood sugar;
weight gain;
low potassium;
swelling in your hands and feet;
skin rash, itching, redness, or swelling; or
thickening or hollowing of the skin where you injected the medicine.
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.
 Novolog side effects (more detail)
Before taking this medicine
You should not use NovoLog if you are allergic to insulin aspart, or if you are having an episode of hypoglycemia (low blood sugar).
NovoLog is not approved for use by anyone younger than 2 years old. This medicine should not be used to treat type 2 diabetes in a child of any age.
To make sure NovoLog is safe for you, tell your doctor if you have:
liver or kidney disease; or
low levels of potassium in your blood (hypokalemia).
Tell your doctor if you also take pioglitazone or rosiglitazone (sometimes contained in combinations with glimepiride or metformin). Taking certain oral diabetes medicines while you are using insulin may increase your risk of serious heart problems.
Tell your doctor if you are pregnant or breastfeeding.
Follow your doctor's instructions about using insulin if you are pregnant or you become pregnant.
