Taking vitamin B-12 can cause allergic reactions that could lead to a wide range of symptoms. Coughing is a common symptom of developing asthma during an allergic reaction. Stop taking vitamin B-12 if you develop a constant cough along with other symptoms because you may be experiencing a severe allergic reaction. B-12 supplements are not intended for use in a healthy adult because B-12 is stored for many years in soft tissue, according to Drugs.com. B-12 should only be used under a doctor's recommendation.
Vitamin B-12
Vitamin B-12 is commonly used to treat conditions that cause a B-12 deficiency. The vitamin is water soluble, meaning that you cannot overdose on it because an excess amount will be expelled through your urine. Anemia, low iron in the blood, is a common cause of a vitamin B-12 deficiency. Most B-12 vitamin supplements are synthetic versions of B-12 and may cause an allergic reaction when consumed if your immune system doesn't identify the substance as safe.
Allergic Reaction
When you take a vitamin B-12 supplement, your immune system must determine whether or not the substance will harm the body. Although the vitamin supplement is harmless, the immune system causes the body to react as if it were an intruder. This mistake causes a flood of chemicals to attack the supplement, such as immunoglobulin E antibodies and histamine. These chemicals cause your blood vessels to dilate in soft tissue, leading to inflammation and common allergy symptoms.
Coughing
Coughing is a result of swelling in your airways, resulting from inflammation. When your airways swell, your ability to breathe is reduced or cut off completely. Along with coughing you may develop shortness of breath, chest tightness or pain and wheezing. Wheezing is a high-pitched sound that is made from the small amount of air being forced through your throat, according to PubMed Health. Contact emergency medical personnel if you are unable to breathe or you develop other symptoms that are alarming.
Allergy Symptoms
Other symptoms that are commonly associated with an allergic reaction to vitamin B-12 include lightheadedness; dizziness; facial, tongue or lips swelling; skin rashes; hives; eczema; general itching; diarrhea; nausea; and vomiting. A severe allergic reaction could lead to death and needs to be assessed by your doctor. If you notice your heart rate increase and you feel faint, call 911.
