 DRUG ALLERGY

1. Drug reactions could be a) Immediate reactions with urticaria, wheeze, and anaphylaxis. B) Accelerated reactions developing over 1-72 hours with urticaria, anaphylaxis, abdominal pain, wheeze c) Late reactions begin after 72 hours with maculopapular eruptions, drug fever, hemolytic anaemia, serum sickness, nephritis, exfoliative dermatitis, leucopenia, and Steven Johnson syndrome. Could manifest as rhinitis, bronchospasm, and abdominal pain.
2. + The common drugs causing allergic reactions are B-lactams i.e. the Penicillins and cephalosporins, Sulpha, Streptomycin, chlorampheniol, and anaesthetic agents. In Antibiotic allergy, high, intermittent dosing and parenteral administrations are likely to cause reacfions
3. Atopic persons are not at increased risk for antibiotic allergic reactions as generaly believed
4. There is cross reactivity between penicillin and cephalosporins and more than 50% of patients allergic to penicillins might react to cephalosporins and this is less with the later generation of cephalosporins. Other than cephalosporins, the other beta-lactam antibiotics are similar in structure to penicillins but their cross reactivity is undetermined. Skin testing for Non-beta-lactam antibiotics is unreliable.
5. Patch testing’ is of diagnostic value in detecting drug allergy.

General Measures for Patients with Allergies

1. Sleep on synthetic material like foam. Where cotton pillows are used, cover with thin plastic sheet, which should be wiped with moist cloth at bedtime.
2. Do not have any pets in the house. In many cases, there is no choice but to dispense with the pet.
3. Do not have any indoor plants in the house. They larbour insects and dust and can also produce allergenic pollen.
4. No one should smoke at home, and preferably at place of work.
5. Avoid crowded places full of dust and smoke like cinema theatres, closed meeting halls etc.
6. Do not use carpets in the house. They harbour house dust mites, and other dust, which are not removed fully even by vacuum cleaning, leave alone sweeping with brooms.
7. Organise regular pest control for the house for cockroaches, spiders, houseflies, mosquitoes which are very common causes of allergy in India.
8. Mosquito and other repellent fumes often cause respiratory allergy, and should be avoided.
9. No rules can be laid for “food allergies’. It is generally an individual matter.