(BPT) - Anaphylaxis is a severe, life-threatening allergic reaction that can happen at any age. In infants and toddlers, symptoms can escalate quickly. Spotting the early warning signs of anaphylaxis and acting fast can help keep a child safe.

The challenge for parents and caregivers? Infants and toddlers are unable to tell you what's wrong. They don't yet have the words to describe what they're feeling. It's up to you to recognize that something serious may be happening.

That's why it's important to learn the unique symptoms of anaphylaxis in very young children - and know how to respond quickly.

Allergy & Asthma Network, the leading national nonprofit organization dedicated to improving the health of people with asthma, allergies and related conditions, recently launched a new Infant Anaphylaxis online guide. It includes practical information and resources for parents and caregivers.

What is anaphylaxis?

Anaphylaxis occurs when the body's immune system reacts to a substance - such as food, medication, an insect sting or latex - as if it were dangerous. This triggers the release of histamine and other chemicals, leading to a chain reaction of severe symptoms.

The response can affect multiple body systems, including the skin, breathing, digestion, nervous system, and heart. Because babies can't tell you how they feel, the signs are more subtle - and easy to miss.

Without prompt treatment, anaphylaxis can cause swelling of the airways, breathing difficulties, or even shock. Epinephrine is the first line of treatment for anaphylaxis.

What causes anaphylaxis in young children?

Food allergies are the most common cause of anaphylaxis in infants and toddlers. Foods that may cause a reaction include cow's milk, infant formula, eggs or peanut products. Infants may also develop symptoms when a mother consumes a food allergen and it passes into her breast milk.

Certain medications such as penicillin-based antibiotics may cause allergic reactions. Insect venom from a sting and latex are other potential allergic triggers. Latex can be found in bottle nipples, pacifiers and other rubbery products.

Experts now recommended introducing common food allergens to babies at 4-6 months of age. Research shows that when babies eat these foods early and often, their immune systems can learn to accept them instead of reacting to them. This can reduce the risk of food allergies later in life.

If your baby has eczema or already has a food allergy, speak with a pediatrician or pediatric allergist before introducing common food allergens into your child's diet.

What are the symptoms of anaphylaxis in infants and toddlers?

Anaphylaxis can look different in infants and toddlers than it does in older children and adults. Recognizing the early signs is critical. Symptoms can change quickly and may become life-threatening if not treated right away.

It's important for parents and caregivers to watch closely for physical or behavioral changes. Here are some common signs of anaphylaxis in each body system, with additional signs to watch for in infants and toddlers:

Breathing

• Common signs in all ages: shortness of breath, cough, tight or hoarse throat, swelling of lips or tongue that impacts breathing
• Additional signs in infants and toddlers: belly breathing, rapid breathing, nasal flaring, tugging the chest or neck, hoarse cry

Heart

• Common signs in all ages: skin color is pale or has a bluish tint, weak pulse, dizziness or fainting
• Additional signs in infants and toddlers: blotchy discoloration of the skin, fast heartbeat, appearing limp or wobbly with poor head control

Skin

• Common signs in all ages: many hives across the body
• Additional signs in infants and toddlers: obvious swelling on the face

Stomach

• Common signs in all ages: severe vomiting or diarrhea (may be combined with other symptoms)
• Additional signs in infants and toddlers: vomiting more than once, vomiting or diarrhea combined with other symptoms

Behavior

• Common signs in all ages: feeling of "doom," confusion, agitation, altered consciousness
• Additional signs in infants and toddlers: very tired, difficult to wake up, withdrawn, crankiness, inconsolable crying

Symptoms of anaphylaxis may vary among babies and can be different each time a baby has an allergic reaction.

Treating anaphylaxis

Infant anaphylaxis is a medical emergency needing immediate action. Epinephrine is the only medication that effectively treats anaphylaxis. It's key to always have at least two doses on hand, as symptoms can sometimes come back after the first dose is given.

If you think your child has been exposed to a food allergen, or severe symptoms are occurring in one or more body system, give epinephrine right away. If symptoms are mild but occurring in more than one body system, you should also give epinephrine. Seek emergency medical help if your baby's symptoms are severe, come back or worsen after the first dose, or don't go away completely.

Ask your child's pediatrician for an epinephrine prescription for your child. Make sure you feel comfortable giving it. Teach others who care for your child how to administer it.

Learn more at AllergyAsthmaNetwork.org.