Having said this, toothpaste allergies are not very common. If you have used toothpaste earlier as a home remedy for zit and nothing happened, probably this is not the cause for swelling.
There are many causes for lip swelling and one of them is a condition called angioedema which is the result of an allergic reaction. Though the exact cause is not known, some factors which trigger angioedema may include allergy to the following:
- Animal dander (shed skin scales)
- Water or sunlight
- Cold or Heat
- High allergen foods like berries, fish or shellfish, eggs, nuts, and / or milk
- Insect bites and stings
- Drug allergy to antibiotics (example, penicillin or sulfa drugs), no steroid anti-inflammatory drugs and / or blood pressure medicines
- Pollen
- Side effects of other illness or infections. Example, autoimmune disorders such as lupus, leukemia or lymphoma.
Moreover, though the swelling can occur anywhere (on the hands, feet or throat), it usually occurs around the lips and eyes. Swelling associated with angioedema may be painful or itchy. Causes for lip swelling may also include a condition called Oral Allergy Syndrome (OAS), a kind of food allergy, the reaction of which is restricted to the lips, mouth and throat. Symptoms like swelling and itching often worsen in spring and pollen seasons.
If the symptoms of angioedema or OAS is mild, it may require no treatment and may recover on its own in a day or two. However, if the swelling is accompanied by other symptoms such as breathing difficulty, wheezing, fainting etc. call 911 immediately. It is also best to consult a physician if the swelling worsens or if it does not subside in a day.
References:
- http://www.chop.edu/service/allergy/allergy-and-asthma-information/oral-allergy-syndrome.html
- http://www.nlm.nih.gov/medlineplus/ency/article/000846.htm
answered by A S