Saturday 13 May 2017

Allergic Reactions - An Overview: Causes, Symptoms & Treatment

Allergic reactions can range from an irritating itch to a fatal outcome. But knowing how to handle such an emergency can make the vital - sometimes, the life-and-death - difference.
One peaceful Sunday afternoon you're dozing comfortably in a deck-chair when a sudden scream fills the air and your kid brother, running towards from the direction of the public garden, crashes into your solitude. Your blood runs cold - his face is all red and swollen, and he's gasping for breath. A bee has stung him and he's one of those few people who are highly allergic to bee venom.
What do you do to treat an allergic reaction - whether it's caused by a bee sting or fresh strawberries 'n cream? Even if you're a novice at emergency care, our step-by-step guide will tell you what needs to be done before you can reach a doctor.
WHAT HAPPENS - AND WHY
What exactly happens in an allergic reaction? An allergy is an over-reaction of the body's defence mechanism to the introduction of a foreign substance; the symptoms include intense itching, swelling up of body parts, watering of the nose, and breathlessness.
Allergies are of several types, including delayed and chronic ones, but the present article is limited to the management of immediate types of hypersensitivity reactions that can cause a lot of damage in a short time if not treated promptly and correctly.
Materials that can be cause such severe, immediate allergies include:
  • Different kinds of proteins - edible (such as eggs and dals) as well as those used locally.
  • Anti-serum (Snake venom, Tetanus, Rabies etc.)
  • Hormones
  • Enzymes
  • Venom (Bee and hornet stings, etc.)
  • Pollen extracts
  • Foods (Milk, eggs, fish, wheat, strawberries, chocolates etc.)
THE SYMPTOMS
Some common signs of allergy to look for are (System-wise):
Skin: Flushing and redness; itching; urticarial (large, irregular, raised patches with redness and itching); swelling of the skin over a part of the body; bite marks or sting punctures.
Eyes: Redness; swelling; itching; watering.
Respiratory Tract: Sneezing; watering of nose; coughing; breathlessness; chocking; tightness in the chest; suffocation; a sense of something stuck in the throat; inability to talk.
Gastro-intestinal: Vomiting; diarrhea; pain in the throat.
General: Anaphylactic shock - manifests itself in swelling of the face and body, sudden sneezing, dizziness, restlessness, nausea, suffocation and panic and unconsciousness - these symptoms can occur one after the other rapidly and the patient can die in minutes if emergency measures are not started at once.
(It is not necessary that you will find the symptoms of only one system in an allergy - a mix of symptoms may be found.)
Here's how you deal with individual allergies (Source-wise):
ANIMALS
A person can be allergic to the dander, i.e. the fine scales and dust of dried-up skin and hairs on an animal, and can react violently to this alien protein. Cats especially can bring on a violent reaction - most commonly, rhinitis (watering of the nose) and asthma (or breathlessness) which could become severe. Some people are allergic to n animal's saliva.
Remove the offending animal from the victim's presence, and take the sufferer into an open area where he can breathe in fresh air. If he's been licked, immediately wash the area with soap and water. Brush off all tell-tale traces of the animal's hair from the person's clothes. If the contact has been longer and the victim is sneezing or coughing violently and getting more and more breathless by the minute, give him an anti-allergy pill and take him to a doctor.
INSECTS
Bites and stings from insects like ants (especially fire ants), bees, wasps, hornets, and yellow jackets can produce severe allergic reactions in the susceptible; even through their venom is mild. Such reactions include urticarial, nausea, abdominal or uterine cramps, bronchospasm, massive swelling of the face and glottis, breathlessness, bluish skin due to lack of oxygen, low b.p., coma and death.
A word of caution - even normal people can develop severe allergic reactions if bitten in the mouth or throat.
Unlike wasps and ants, bees can leave their stings embedded in the skin. If you have a pair of tweezers, pull out the sting. Or scrape it off carefully with a sharp knife or needle. Do not scratch the bite; this will only spread the venom. If you have an anti-histamine cream or a steroid cream, use it. Even calamine lotion helps. If no cream is available, put ice or cold water on the sting.
Reassure the patient and make him lie down on his back. Loosen tight clothing around the neck and waist so that breathing is not restricted. Cover him with a rug or a blanket. Raise his feet by placing a cushion or folded coat below them. Do not offer the victim anything to eat or drink and don't let him smoke - it may choke him further.
If breathing starts getting difficult or if he begins to lapse into unconsciousness, take him to a hospital immediately. While transporting him or waiting for help, turn him to one side so that he does not choke on his vomitus.
If he has stopped breathing, give him mouth-to-mouth resuscitation or chest compression by putting him flat on his back and placing the balls of your palms on his breast-bone and pressing down at intervals of a few seconds.
Some large caterpillars, especially Gypsy Moths, can cause severe reactions due to the chemicals in their hairs. Brush off the insect with a twig and remove the hairs by pressing down some leucoplast or cellotape or dough on the area and pulling up - do this in different directions till all the hairs have come off. If allowed to remain the chemicals in the hairs can cause more damage.
Put ice on the area, wash with a lot of cold running water, and apply anti-histamine or steroid cream. Swallow an anti-histamine tablet and go to a doctor.
FOODS
Some people can develop nasty, even fatal reactions to certain food stuffs. Some common culprits include protein-containing foods like nuts, cow's milk, hen's eggs, soya beans, fish and sea-food; sunflower seeds, chamomile tea, peanuts, bananas, sesame (til) oil and food additives like metabisulfites - which are common in beer and Chinese food.
Food allergies occur mainly in children.
Reactions may be classified as:
EARLY REACTIONS (Less than two hours): Asthma; Abdominal Pain; Vomiting; Urticaria; Anaphylaxis; Diarrhoea; Rhintis; Angio-oedema (Swelling); Dermatitis.
LATE REACTIONS (More than two hours): Asthma; Gastro-intestinal bleeding with anaemia; Growth retardation; Urticaria and Dermatitis; Alveolitis (Inflammation inside the lungs); Malabsorption, diarrhoea; Protein-losing enteropathy; Vomiting
Severe diarrhoea, including vomiting, can develop 12-36 hours after the ingestion of certain foods like cow's milk. If this happens in infants who are being weaned for the first time, rapid dehydration can occur if remedial measures are not undertaken immediately. Plenty of fluid should be given orally and the international Oral Rehydration Therapy (ORT) which consists of one glass of boiled and cooled water + the juice of one lemon + 4-5 teaspoonsful of sugar + a pinch of salt should be stirred and sips of this given several times a day, as much as the patient can take. The initial vomiting should not be stopped because it might help to bring out some of the allergy-causing food.
Asthma, or sudden breathlessness, can be relieved by taking the patient out into an open space and making him do slow, deep-breathing exercises. An anti-allergy pill may help as also an anti-asthma. The patient should be reassured, calmed down and made to sit in a propped-up position as lying down may aggravate the asthma.
Abdominal pain can be relieved with a hot-water bottle, drinking plenty of water, and mint juice + honey or a tiny pinch of asafetida or aniseed.
Urticaria can be relieved by applying cold water and calamine lotion.
Sneezing can be controlled by pressing the area just below the nostrils with a finger.
Rhintis or watering of the nose will be relieved with an anti-allergy pill.
If swelling of the face, hands and feet begins, take the patient quickly to a hospital or to a doctor, because this is a serious portent.
DRUGS
Many drugs can cause mild to moderate allergic reactions like nausea, vomiting, loose motions, pain in the abdomen, rhinitis, asthma, skin irritation, urticaria, burning in the stomach, dark skin patches, white skin patches, headaches and watering of the eyes. Locally-used products like creams can cause redness and swelling of the skin and rashes.
Some drugs can even cause severe anaphylactic shock. These include Aspirin, Penicillin, Sulphonamides, Streptokinase enzyme (used in the treatment of heart attacks), Indomethacin Iodine dyes used for x-rays, Tetanus and Rabies Anti sera, Streptomycin and even Liver extract and Vitamins.
Some medicine like the anti-malarials - Chloroquine and Primaquine - and drugs like Nitrofurantoin and Ciplofloxacin (an antibiotic) can cause breaking up of the red blood cells if the person has a G 6 PD Enzyme deficiency in the blood.
Many asthmatics can suffer severe aggravation of their symptoms with certain drugs like the anti-inflammatory ones - Ibuprofen, Acetyl Salicyclic acid, Indomethacin, Mefenamic Acid. Many normal people can also get a bout of debilitating Asthma or Rhinitis with these drugs because they can cause obstruction of the upper and lower airway tracts, giving rise to a life-threatening episode.
When an allergic reaction to an injection occurs, starting with intense itching and swelling at the site of the injection, then generalized itching all over the body, urticarial rashes, tightness in the throat and other symptoms, immediately tie a rubber tourniquet 2'' or so above the site of injection to prevent further spread (this method can be employed in a bee sting as well); then use all the methods suggested for treating anaphylactic shock while you're preparing to take the victim to a doctor.
If a drug has been taken orally and causes early allergic manifestations, try to encourage or induce vomiting by giving the person a mugful of water into which a tablespoonful of salt has been added. If given within an hour of swallowing the medicine, quite a lot of the drug can be brought out, thus minimizing its effects.
Calm the patient and help him lie down with his head turned to one side, feet raised. Keep him warm.
Keep the mouth passage free from vomitus or any other obstruction.
If he's conscious and not vomiting, give him plenty of water to drink; this will dilute the drug. If you have an anti-allergy pill give it to him. Even cold tablets can help in such a situation. If these are not available, give him a tablespoon of some antacid.
Make sure to take down the name of the drug that he has taken or retrieve its wrapper from the waste-basket before going to a hospital. Show the name of the drug to the doctor there so that he can give the necessary antidote.
Certain drugs can cause Dyskinesia - nerve complications like twisting, deviation or trembling of the lips and face into abnormal shapes and movements. The drugs that give rise to dyskinesia are anti-psychotics like Chlorpromazine, Trifluperazine, Stemetil etc. The treatment for dyskinesia is Dazepam tablets or injection.
For pruritus or itching of the skin, taking cool baths helps as well as applying grease or unscented oils to the skin just after a bath. Cool, loose cotton clothing also helps. Avoid extremes of temperature.
CONTACT DERMATITIS
Irritation of the skin can occur with detergents, creams, local medication, hair dyes, leather slippers, plastic objects, rubber gloves, solvents, cleaners, metal coins, jewellery, bleaches, insecticides, cosmetics, adhesives, petrol etc.
Wash the skin thoroughly with soap and water, and then rinse with plenty of running water. Cold milk soaks might be helpful, as also topical cortisone creams.

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