Signs of Vitamin Deficiency in Children Every Parent Should Know

Children need a wide range of vitamins and minerals to support healthy growth, brain development, immunity, bones, blood production, vision, and normal energy levels. Because children are growing rapidly, nutritional gaps can sometimes become more important than they appear.

The challenge for parents is that nutrient deficiencies rarely announce themselves with one unmistakable symptom. A child who is unusually tired may have iron deficiency, poor sleep, an infection, or another health problem. Frequent illness may be related to nutritional inadequacy, but it can also be normal for young children who are regularly exposed to viruses. Slow growth may be associated with inadequate zinc or other nutrients, but it can also have many medical and genetic causes.

For that reason, knowing the possible signs of vitamin deficiency in children is useful for recognizing when a conversation with a pediatrician or qualified healthcare professional may be appropriate. It is not a substitute for testing or medical diagnosis.

Micronutrient deficiencies remain a significant global health issue. The CDC notes that at least half of children under 5 worldwide experience deficiencies in vitamins or minerals. Globally, anemia affects about 40% of children under 5, while vitamin A deficiency affects an estimated 190 million preschool-age children.

This guide explains the most important signs parents should know, which nutrients are commonly involved, who is at higher risk, what foods can help, when testing may be needed, and why supplements should not be given automatically.

What Is a Vitamin or Micronutrient Deficiency?

A nutrient deficiency occurs when the body does not have enough of a particular vitamin or mineral to meet its needs.

Strictly speaking, vitamins and minerals are different categories. Vitamins include nutrients such as vitamins A, C, D, E, and the B vitamins. Minerals include iron, zinc, calcium, iodine, and others.

However, parents and healthcare websites often use the broader phrase “vitamin deficiency” to describe inadequate micronutrient intake generally.

A child can develop a deficiency for several reasons:

• The child’s diet may lack enough nutrient-rich foods.
• The child may eat an extremely limited variety of foods.
• Rapid growth may increase nutrient requirements.
• A digestive disorder may interfere with nutrient absorption.
• Certain chronic illnesses may increase nutritional needs or losses.
• Some children may have dietary restrictions that require careful nutritional planning.
• Infants may have specific supplementation needs.
• Excessive intake of one supplement can sometimes interfere with another nutrient.

Importantly, a deficiency does not always mean that parents have done something wrong. Children have different nutritional needs, and some deficiencies are related to medical conditions or absorption problems rather than simply food choices.

Common Signs of Vitamin Deficiency in Children

There is considerable overlap between nutritional deficiency symptoms and ordinary childhood illnesses. Still, certain patterns deserve attention.

Possible warning signs include persistent fatigue, unusual weakness, pale skin, poor appetite, slow growth, frequent infections, delayed wound healing, changes in vision, bone or muscle pain, hair loss, mouth or tongue changes, bleeding gums, developmental concerns, and unusual cravings such as eating non-food substances.

The key word is persistent.

One day of tiredness or a few days of reduced appetite does not automatically indicate a vitamin deficiency. Parents should pay more attention when symptoms persist, occur together, interfere with daily activities, or appear alongside poor growth or an unusually restricted diet.

1. Iron Deficiency: Tiredness, Pale Skin, Weakness and Poor Concentration

Iron deficiency is one of the most important nutritional deficiencies to recognize in children.

Iron is a mineral rather than a vitamin, but it is frequently discussed alongside childhood vitamin deficiencies because of its major role in blood production and development. Iron is needed to make hemoglobin, which carries oxygen throughout the body. It also supports brain development and the ability to grow, pay attention, and learn.

Possible signs of iron deficiency or iron-deficiency anemia include:

• Persistent tiredness
• Weakness
• Pale or unusually dull-looking skin
• Irritability
• Reduced attention
• Headaches or dizziness
• Shortness of breath in more significant anemia
• Reduced appetite
• Pica, meaning cravings for non-food substances such as ice, dirt, paper, or clay

The American Academy of Pediatrics notes that at least 15% of toddlers in older U.S. data showed signs of iron deficiency, while recent guidance emphasizes screening and risk assessment across childhood and adolescence.

Iron requirements also change substantially with age. According to the NIH Office of Dietary Supplements, children ages 1–3 need about 7 mg of iron daily, children ages 4–8 need 10 mg, children ages 9–13 need 8 mg, and teenagers have different needs depending on sex, with adolescent girls requiring 15 mg per day.

Foods that provide iron

Good sources include lean meat, poultry, seafood, eggs, lentils, beans, peas, nuts, seeds, leafy green vegetables, and iron-fortified cereals and breads.

Vitamin C can improve absorption of non-heme iron from plant foods. For example, lentils can be paired with tomatoes, citrus fruit, strawberries, bell peppers, or broccoli.

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2. Vitamin D Deficiency: Bone Pain, Muscle Weakness and Rickets

Vitamin D is essential for calcium absorption and healthy bones. Severe deficiency in growing children can cause rickets, a condition in which developing bones become soft and poorly mineralized.

Possible signs can include:

• Bone pain or tenderness
• Muscle weakness
• Delayed motor development
• Difficulty walking in severe cases
• Bowed legs or other skeletal abnormalities
• Poor growth
• Dental abnormalities
• In severe cases, seizures caused by low calcium

The NIH explains that severe vitamin D deficiency in children can result in rickets, while the CDC states that all children need vitamin D beginning shortly after birth.

For reference, the NIH lists an adequate intake of 400 IU (10 mcg) per day for infants from birth through 12 months and 600 IU (15 mcg) per day for children and teenagers.

Breastfed infants generally need vitamin D supplementation because breast milk does not usually provide enough vitamin D on its own. The CDC recommends 400 IU daily beginning shortly after birth for breastfed infants and infants receiving both breast milk and formula.

Vitamin D status can be influenced by diet, sunlight exposure, skin pigmentation, geography, air pollution, clothing, and other factors. Therefore, simply assuming that a child gets enough vitamin D from sunlight is not always appropriate.

Parents should not intentionally expose babies to excessive direct sunlight to obtain vitamin D. Infant sun-safety recommendations should be followed.

Internal linking opportunity: A useful related article would be “Vitamin D for Children: Benefits, Food Sources and Supplement Needs.” If your website offers pediatric nutrition consultation, this section can also link naturally to that service.

3. Vitamin A Deficiency: Night Blindness and Eye Problems

Vitamin A plays an important role in vision, immune function, growth, and development.

One of the most characteristic signs of vitamin A deficiency is difficulty seeing in low light, known as night blindness. More advanced deficiency can cause xerophthalmia, which can damage the cornea and potentially result in permanent vision loss.

Other possible consequences include greater susceptibility to certain infections and anemia.

Vitamin A deficiency is not equally common everywhere. It is rare in many high-income settings but remains an important public health problem in several low- and middle-income countries.

The WHO estimates that approximately 190 million preschool-age children are affected by vitamin A deficiency, particularly in Africa and Southeast Asia.

A pooled analysis of surveys from 138 low- and middle-income countries estimated vitamin A deficiency in 29% of children aged 6 months to 5 years in 2013, with particularly high prevalence in South Asia and sub-Saharan Africa.

Vitamin A food sources

Vitamin A can come from preformed vitamin A in foods such as eggs, dairy products, fish, and liver, as well as provitamin A carotenoids found in foods such as carrots, sweet potatoes, pumpkin, spinach, and other colorful fruits and vegetables.

Parents should be cautious with high-dose vitamin A supplements, however. Excess preformed vitamin A can be toxic.

Internal linking opportunity: Link to “Healthy Snacks for Kids” or “Child Nutrition by Age” with anchor text such as “vitamin-rich foods for children.”

4. Vitamin B12 Deficiency: Fatigue, Developmental Changes and Nerve Symptoms

Vitamin B12 is important for red blood cell formation and normal nervous-system function.

A child with B12 deficiency may experience:

• Fatigue or weakness
• Pale skin
• Reduced appetite
• Poor growth
• Mouth or tongue soreness
• Numbness or tingling
• Balance problems
• Developmental delays in infants
• Memory or concentration problems
• Neurological symptoms in more serious cases

The NIH notes that infants with vitamin B12 deficiency can develop failure to thrive, developmental delays, and megaloblastic anemia. Importantly, neurological injury can occur even without obvious anemia.

Children may be at greater risk when their diets contain little or no animal-source food unless appropriate fortified foods or supplements are included. Malabsorption conditions can also contribute.

Because B12 deficiency can have neurological consequences, persistent developmental or neurological symptoms warrant medical evaluation rather than simply starting a multivitamin.

Internal linking opportunity: If your website has content about picky eating, vegan or vegetarian diets for children, or pediatric nutrition consultation, this is a strong contextual internal-link location.

5. Folate Deficiency: Fatigue, Weakness and Mouth Changes

Folate, also called vitamin B9, is needed for DNA synthesis and cell division. Children need it during periods of rapid growth.

Folate deficiency can contribute to megaloblastic anemia, causing symptoms such as:

• Fatigue
• Weakness
• Irritability
• Difficulty concentrating
• Headaches
• Shortness of breath
• Heart palpitations
• Mouth or tongue sores
• Changes involving the skin, hair, or nails

According to the NIH, recommended folate intake rises with age, from 150 mcg DFE per day for children 1–3 years to 200 mcg for ages 4–8, 300 mcg for ages 9–13, and 400 mcg for teenagers ages 14–18.

Folate is found in leafy green vegetables, beans, peas, nuts, citrus fruits, and fortified grain products.

Folate deficiency is relatively uncommon in populations with adequate access to fortified foods, but it can occur in children with highly restricted diets or malabsorption conditions.

6. Vitamin C Deficiency: Bleeding Gums and Poor Wound Healing

Vitamin C deficiency is uncommon in many developed countries, but it can occur when a child’s diet is extremely limited.

Severe vitamin C deficiency causes scurvy.

Possible symptoms include:

• Fatigue
• Weakness
• Swollen or bleeding gums
• Easy bruising
• Small red or purple spots on the skin
• Joint pain
• Poor wound healing
• Corkscrew-shaped hairs
• Loose teeth in severe cases

The NIH reports that signs of scurvy can develop within about one month of consuming very little vitamin C, particularly below approximately 10 mg per day, although the timeline varies according to existing body stores.

Children with extremely selective eating patterns can be at increased risk because vitamin C is concentrated in many fruits and vegetables.

Useful food sources include oranges and other citrus fruits, strawberries, kiwi, tomatoes, bell peppers, broccoli, and potatoes.

Internal linking opportunity: Connect this section to an article such as “Healthy Snacks for Kids” with anchor text like “vitamin C-rich foods for children.”

7. Zinc Deficiency: Slow Growth, Poor Appetite and Frequent Infections

Zinc is a mineral involved in immune function, DNA and protein synthesis, growth, wound healing, and taste and smell.

Potential signs of zinc deficiency in children include:

• Poor appetite
• Slow growth
• Diarrhea
• Hair loss
• Frequent infections
• Changes in taste or smell
• Delayed wound healing

The NIH specifically identifies slow growth, diarrhea, and loss of appetite as signs in infants and children, while older children may experience hair loss and frequent infections.

Zinc requirements increase as children grow. The NIH lists 3 mg daily for children ages 1–3, 5 mg for ages 4–8, 8 mg for ages 9–13, and 9–11 mg for teenagers depending on sex.

Food sources include meat, seafood, eggs, dairy products, beans, nuts, whole grains, and fortified cereals.

It is important not to assume that frequent colds automatically mean zinc deficiency. Young children commonly experience repeated respiratory infections because of exposure to new viruses, especially in daycare and school environments.

8. Vitamin E Deficiency: Rare but Possible in Specific Conditions

Vitamin E is an antioxidant that helps protect cells and also supports immune and neurological function.

Vitamin E deficiency is uncommon in healthy children who eat a varied diet. It is more likely to occur in children with certain disorders involving fat absorption or metabolism.

When deficiency is clinically significant, symptoms may include neurological problems, muscle weakness, vision problems, and immune dysfunction.

The NIH lists recommended vitamin E intake at 6 mg per day for children ages 1–3, 7 mg for ages 4–8, and 11 mg for ages 9–13.

Good food sources include nuts, seeds, vegetable oils, spinach, broccoli, and some fortified foods.

Because true vitamin E deficiency is relatively uncommon, unexplained neurological or muscular symptoms should not be self-treated with high-dose vitamin E.

9. Iodine Deficiency: Growth and Thyroid-Related Concerns

Iodine is required for the production of thyroid hormones, which regulate metabolism and are particularly important for brain development and growth.

A deficiency can interfere with normal thyroid hormone production. In severe or prolonged deficiency, children may develop thyroid enlargement, growth problems, and developmental impairment.

Iodized salt is one of the most important public-health strategies for preventing iodine deficiency. However, parents should not respond to concerns about iodine by giving children iodine supplements without medical guidance. Excess iodine can also cause health problems.

The exact dietary needs of children depend on age, and iodine status can be influenced by the type of salt and other foods consumed.

Internal linking opportunity: If your website has an article about “Essential Minerals for Children” or a pediatric nutrition service page, this section provides a natural internal-link opportunity.

A Quick Guide to Symptoms and Possible Nutrient Deficiencies

Possible sign	Nutrients that may be involved	Important note
Persistent tiredness	Iron, B12, folate	Also occurs with sleep problems, infections and other conditions
Pale skin	Iron, B12, folate	Requires evaluation if persistent
Poor growth	Zinc, vitamin D, overall nutrition	Many non-nutritional causes are possible
Bone pain or bowed legs	Vitamin D	Severe deficiency can cause rickets
Night blindness	Vitamin A	Requires prompt medical assessment
Bleeding gums	Vitamin C	Dental disease can also cause gum bleeding
Poor wound healing	Zinc, vitamin C	Diabetes and other conditions can also affect healing
Hair loss	Zinc and other causes	Hair loss has many possible explanations
Frequent infections	Zinc, vitamin A and overall nutrition	Recurrent infections are not automatically nutritional
Developmental delay	B12, severe nutrient deficiencies and many other causes	Needs professional assessment
Pica	Iron deficiency	Can have other behavioral or medical causes
Poor appetite	Zinc and other nutrient deficiencies	Also common during ordinary childhood illnesses

This table should be used as a starting point for discussion, not as a diagnostic checklist.

Which Children Are More Likely to Develop Nutrient Deficiencies?

Some children have a higher risk of nutritional deficiencies than others.

Children with highly restricted diets

A child who eats only a small number of foods may miss important sources of iron, zinc, vitamin C, vitamin A, B12, or other nutrients.

Picky eating is common in childhood, but an extremely restricted diet that excludes entire food groups deserves attention.

Infants

Infants have unique nutritional requirements. For example, breastfed infants generally require vitamin D supplementation beginning shortly after birth because breast milk usually does not provide enough vitamin D.

Iron requirements also change considerably after infancy begins, making complementary feeding important.

Children with gastrointestinal disorders

Conditions affecting the intestine can interfere with nutrient absorption. Celiac disease, inflammatory bowel disease, and other digestive disorders may increase the risk of deficiencies.

Children following vegetarian or vegan diets

Well-planned plant-based diets can provide many essential nutrients, but parents need to pay particular attention to nutrients such as B12, iron, zinc, calcium, vitamin D, and iodine.

A child’s nutritional plan should be age-appropriate and individualized rather than based on adult dietary advice.

Children experiencing rapid growth

Growth spurts increase nutritional requirements. This is particularly relevant during infancy and adolescence.

Children with chronic medical conditions

Some health conditions can affect appetite, absorption, metabolism, or nutrient requirements. In these situations, nutritional monitoring may be part of routine medical care.

How Doctors Diagnose Vitamin Deficiency in Children

Parents should avoid diagnosing a deficiency based solely on symptoms.

A pediatrician may begin with the child’s medical history, diet, growth pattern, physical examination, medications, and underlying health conditions.

Depending on the suspected deficiency, testing may include blood tests such as:

• Complete blood count
• Ferritin and iron studies
• Vitamin B12
• Folate
• 25-hydroxyvitamin D
• Vitamin A or related tests in selected situations
• Zinc testing in appropriate clinical circumstances
• Thyroid-related tests when iodine or thyroid dysfunction is suspected

Not every child needs every test.

For example, tiredness alone does not necessarily justify a broad vitamin panel. Testing should generally be guided by symptoms, risk factors, diet, growth concerns, physical findings, and clinical judgment.

When Should Parents Talk to a Pediatrician?

Arrange a medical assessment if your child has persistent or unexplained symptoms such as:

• Ongoing fatigue or weakness
• Significant pallor
• Poor growth or unexpected weight changes
• Persistent diarrhea
• Recurrent or unusual infections
• Bone pain or muscle weakness
• Developmental regression or delay
• Persistent appetite problems
• Bleeding gums or unexplained bruising
• Significant hair loss
• Night-vision problems
• Pica
• Symptoms associated with a highly restricted diet

Some symptoms require more urgent evaluation. Difficulty breathing, fainting, severe weakness, seizures, significant dehydration, altered consciousness, or rapidly worsening symptoms should not be treated as a suspected vitamin deficiency at home.

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Can a Multivitamin Prevent Vitamin Deficiency?

Not necessarily.

A multivitamin may be appropriate for some children, particularly when recommended by a healthcare professional, but supplements are not a replacement for a balanced diet.

Different supplements contain different amounts of nutrients, and some vitamins can be harmful in excessive doses.

This is especially important with fat-soluble vitamins such as vitamins A, D, E, and K, which can accumulate in the body.

Iron supplements also should not be given casually. Excess iron can be dangerous, especially in young children.

The same principle applies to zinc. The NIH warns that excessive zinc intake over time can lower copper levels and impair immune function.

Parents should therefore avoid the assumption that “more vitamins” automatically means “better health.”

Food First: Building a Nutrient-Rich Diet for Children

For most children, the foundation of nutritional adequacy is a varied diet rather than a collection of supplements.

A balanced eating pattern can include:

• Fruits such as oranges, bananas, berries, mangoes and other seasonal choices
• Vegetables, particularly dark green and brightly colored vegetables
• Whole grains and fortified grain products
• Beans, lentils, chickpeas and peas
• Eggs
• Dairy products or appropriate fortified alternatives
• Fish and seafood where culturally and medically appropriate
• Lean meats and poultry
• Nuts and seeds when age-appropriate and safe from a choking perspective

Variety matters because different foods supply different nutrients.

For example, lentils can contribute iron and folate, citrus fruits can provide vitamin C, eggs provide several micronutrients, dairy and fortified alternatives can provide calcium and vitamin D, and meat and seafood can provide highly bioavailable forms of iron and zinc.

The goal is not to make every meal nutritionally perfect. It is to create a consistent dietary pattern that supplies a broad range of nutrients over time.

How Parents Can Reduce the Risk of Nutritional Deficiencies

Parents can take several practical steps without turning mealtimes into a battle.

First, offer a variety of foods repeatedly. Children may need multiple exposures before accepting a new food.

Second, include sources of protein and nutrient-dense foods regularly.

Third, combine plant-based iron sources with vitamin C-rich foods to improve iron absorption.

Fourth, pay attention to growth rather than focusing only on appetite. A child who is eating selectively but growing appropriately may have a different nutritional situation from a child whose restricted diet is accompanied by poor growth.

Fifth, discuss supplements with a pediatrician when a child has a restrictive diet, chronic illness, malabsorption disorder, or other risk factor.

Finally, attend routine pediatric checkups so growth, development, dietary patterns, and risk factors can be monitored over time.

Internal linking opportunity: Your existing content on “Healthy Weight for Kids: Nutrition Tips by Age” can support this section. Other useful internal links include “Picky Eating in Children,” “Child Nutrition by Age,” “Healthy Snacks for Kids,” and “Child Development Milestones.”

Vitamin Deficiency vs. Normal Childhood Symptoms

One of the most important messages for parents is that symptoms alone rarely identify a specific deficiency.

For example, fatigue can occur because of insufficient sleep, infection, stress, iron deficiency, anemia, thyroid disease, or other conditions.

Similarly, frequent infections can be normal in young children exposed to daycare or school environments. Poor appetite may occur during a viral infection. Hair loss can have dermatological, hormonal, nutritional, or other causes.

This is why a symptom such as “my child is tired” should not automatically become “my child needs iron.”

A good clinical approach looks at the complete picture: symptoms, duration, severity, diet, growth, development, medical history, physical findings, and appropriate laboratory testing.

Why Growth and Development Are Important Clues

Nutrition affects more than body weight.

Adequate micronutrient intake supports the development of the brain, nervous system, bones, muscles, blood, immune system, and other tissues.

The CDC specifically notes that micronutrients are essential for healthy development, growth, disease prevention, and well-being.

For parents, this means nutritional assessment should not focus exclusively on whether a child looks thin or has a normal weight.

A child can have an apparently normal body size while still having a nutrient deficiency.

Conversely, a child who is small or growing slowly does not necessarily have a vitamin deficiency.

Growth charts, developmental milestones, dietary history, and medical evaluation provide much more useful information than appearance alone.

Final Takeaway

The signs of vitamin deficiency in children can be subtle, and many overlap with ordinary childhood problems. Persistent fatigue, pallor, poor growth, appetite changes, developmental concerns, bone or muscle symptoms, night-vision problems, bleeding gums, poor wound healing, hair loss, or frequent infections may justify a closer look at a child’s nutritional status.

Iron, vitamin D, vitamin A, vitamin B12, folate, vitamin C, zinc, iodine, and other micronutrients each have different roles and different deficiency patterns. The most useful approach is therefore not to diagnose a deficiency from one symptom, but to look at the child’s overall diet, growth, development, health history, and clinical findings.

A varied, nutrient-dense diet is the foundation of healthy childhood nutrition. When a child has a restricted diet, chronic medical condition, absorption problem, unusual symptoms, or growth concerns, professional nutritional assessment can help determine whether testing or supplementation is actually needed.

Medical disclaimer: This article is for general educational purposes and does not diagnose, treat, or prevent a vitamin or mineral deficiency. Nutritional requirements vary by age, health status, diet, and individual circumstances. Parents should speak with a pediatrician or qualified healthcare professional before giving a child high-dose vitamins, iron, zinc, vitamin A, or other nutritional supplements.

Frequently Asked Questions 

What are the most common signs of vitamin deficiency in children?

Common possible signs include persistent tiredness, pale skin, poor appetite, slow growth, frequent infections, bone or muscle problems, developmental concerns, mouth changes, poor wound healing, and unusual cravings such as pica. However, these symptoms have many possible causes and do not prove a nutrient deficiency.

How can I tell if my child has a vitamin deficiency?

You usually cannot determine this reliably from symptoms alone. A pediatrician may assess the child’s diet, growth, development, medical history, physical findings, and risk factors and may order targeted blood tests when appropriate.

Which vitamin deficiency causes tiredness in children?

Iron deficiency is an important possibility, particularly when tiredness occurs with pallor, weakness, poor concentration, headaches, or pica. Vitamin B12 and folate deficiencies can also cause anemia and fatigue. Other medical conditions can produce the same symptoms.

What are the signs of vitamin D deficiency in kids?

Severe vitamin D deficiency can cause rickets, bone pain, muscle weakness, poor growth, delayed motor development, and skeletal abnormalities. Mild deficiency may not cause obvious symptoms, which is one reason testing should be guided by clinical risk rather than symptoms alone.

What does vitamin A deficiency look like in children?

Night blindness, or difficulty seeing in dim light, is a classic early sign. More severe deficiency can cause xerophthalmia and vision damage. Vitamin A deficiency is also associated with increased vulnerability to some childhood infections.

Can picky eating cause vitamin deficiency?

It can, particularly when a child’s diet is extremely restricted and excludes major food groups for a prolonged period. The specific risk depends on which foods are avoided. A pediatrician or pediatric dietitian can help identify nutritional gaps without unnecessarily restricting the child’s diet further.

Can a child have a vitamin deficiency at a normal weight?

Yes. Body size does not reliably indicate micronutrient status. A child can have an appropriate weight while having inadequate intake or absorption of a specific nutrient.

Should I give my child a multivitamin?

Some children may benefit from supplementation, but not every child needs a multivitamin. The appropriate supplement and dose depend on age, diet, medical history, and nutritional risk. High doses of certain vitamins and minerals can be harmful, so supplements should not be used as a substitute for professional assessment.

Does frequent sickness mean my child has a vitamin deficiency?

Not necessarily. Young children can experience many respiratory and gastrointestinal infections, particularly after starting daycare or school. Nutritional deficiencies can affect immune function, but recurrent illness has many possible explanations.

When should I see a doctor about suspected vitamin deficiency?

Consult a pediatrician if symptoms are persistent, severe, unexplained, associated with poor growth or development, or occur in a child with a highly restricted diet or a condition that may affect nutrient absorption. Urgent medical care is appropriate for serious symptoms such as seizures, difficulty breathing, fainting, severe weakness, or altered consciousness.