Adverse Drug Reaction

Adverse Drug Reaction

Today we often hear a person experiences because of drug allergy. If someone is vomiting after taking the drug? A dry mouth after taking the drug if including allergy medication? If someone is experiencing redness of the skin after taking certain drugs can be ascertained whether the person has an allergy drug or drug side effects? Often we immediately label drug allergies when a person experiences a state that does not fit or are not expected after taking certain medications.

Adverse drug reaction (ADR) is a state / condition does not match expectations / objectives that emerged after drug administration in appropriate doses, in a manner consistent with the goals of treatment. Undesirable effects (ADR) can be caused by our immune system response may also arise not because of our immune system. Then ADR caused by the immune system is divided into 4 which we call types of hypersensitivity according to Gell and Coombs :

Type I
IgE-mediated mast cell attached to the mast cells then release histamine and inflammatory substances that cause symptoms of urticaria, angioedema, airway narrowing (bronchospasm), hives, vomiting, diarrhea, anaphylaxis. Incurred within a period of minutes and hours after drug exposure.

Type II
Cytotoxic; IgG and IgM antibodies specific to the cell which is coated by proteins which are considered allergens / foreign body to destroy it, which gives the symptoms of anemia, deficiency of white blood cell levels and platelet deficiency. Length of time varies.

Type III
Complex Immune; accumulation of antibody-drug complexes that stimulate the activation of the complement triggering inflammatory reactions. The symptoms of serum are sickness, fever, rash, joint pain, enlarged lymph nodes, urticaria, glomerulonephritis, inflammation of blood vessels (vasculitis). Arise 1-3 weeks after drug exposure

Type IV
Delayed type reaction. Section drugs presented to T cells that cause the release of inflammatory substances. Form of allergic contact dermatitis. Arise 2-7 days after exposure to the drug.

Drug allergy is a hypersensitivity reaction mediated by IgE. So which is expressed as a true drug allergy is a hypersensitivity reaction of Type I.
ADR can also occur through pathways not mediated by the immune system, namely:

Can be estimated:

• Drug side effects: dry mouth because antihistamines
• Aftereffect due to the use of drugs: a fungal infection due to long-term antibiotics
• Drug toxicity: liver damage due to methotrexate
• Drug interactions: seizures because theophylline taken with erythromycin
• Overdose: seizures due to excessive use of lidocaine

Can not be predicted:

• Pseudoalergi: resembling anaphylactic reaction after the injection of radioactive contrast material
• Idiosyncrasy: hemolytic anemia in patients with G6PD deficiency after primaquine drinking
• Intolerance: ringing in the ears after drinking even low-dose aspirin

Recognizing hypersensitivity to the drug
Any allergic-like symptoms such as urticaria, anaphylaxis and asthma should consider the possibility of drug hypersensitivity. Other symptoms such as serum sickness (redness at the edge of the hand, fingers, toes, soles of the feet), rash, fever, hepatitis, lupus-like syndrome, acute interstitial nephritis, pulmonary infiltrate with eosinophilia also have to think about the possibility of drug hypersensitivity.

The main one is a history of drug use must be recorded in full, including:

• Types of drugs, both prescription drugs, OTC drugs, vitamins, minerals, supplements
• Drug exposure time
• Route medicine: whether oral, injection into muscle or injection into a vein or topical medications / topical. Providing topical, via injection in the muscle and blood vessels provide the possibility of drug hypersensitivity, while giving orally lower likelihood
• History of symptoms that appear on previous drug exposure

Physical examination that should be seen if there is a sign of the gravity of the ADR:

Urticaria with edema of the larynx (difficult breathing, rough breathing), wheezing, hypotension (low systolic blood pressure <100mgHg).

And signs of serious reactions such as ADR:
Fever, sores in the mucous membranes (eye cornea, mouth, vagina, anus, penis), enlarged lymph nodes, swollen and painful joints or abnormal lung examination

Serious ADR include Stevens Johnson syndrome and toxic epidermal necrolisis. This situation is an immunologically mediated ADR but are not part of the type hypersensitivity Types I-IV.

Investigations
Examination to support the diagnosis of hypersensitivity or allergy medications can be done in the form:

• Suspected type I hypersensitivity reaction: skin allergy tests, RAST, serum triptase.
• Suspected Type II hypersensitivity reaction: coomb director and indirect tests
• Suspected Type III hypersensitivity reaction: erythrocyte sedimentation rate, CRP, complement levels (C3, C4), anti-nuclear antibodies, antibody antihiston
• Suspected Type IV hypersensitivity reaction: the skin patch test (patch test)

Diagnosis
Diagnosis of clinical symptoms, history of exposure to drugs and assisted with the investigation. When the diagnosis of drug hypersensitivity has upheld the termination of the drug is a major step. An alternative drug that does not have a structure similar to drug hypersensitivity causes should be sought. Besides stopping the drug, is managing supportive. Corticosteroids, antihistamines and bronchodilators are given according to symptoms. If a severe hypersensitivity reaction, it can be considered giving epinephrine.

Prevention
Drugs that are known to cause hypersensitivity should be recorded and should not be given back. The drug should be informed of health personnel, if necessary can be made on patient information (a bracelet, necklace signs of allergy / hypersensitivity).

Giving drugs originally based on an indication, because the administration of drugs as indicated in the right dose it still have the possibility of causing ADR. If not then do not need drugs to use drugs because the drug remains a chemical that can cause unwanted effects.