Selective decrease in IgA is seen with administration of:

Ans: A (Phenytoin) Ref: Goodman & Gillman's The Pharmacological Basis of Therapeutics, 2011, 12th Edition, McGrow Hid, Burton LL, P 593Explanation:Phenytoin can cause lymphadenopathv similar to Hodgkin's disease and malignant lymphoma. This is attributed to decrease in IgA production.Other Adverse Effects of PhenytoinNeurologicHorizontal gaze nystagmusSedationCerebellar ataxiaCerebellar atrophyOphthalmoparesisSeizuresHematologicMegaloblastic anemiaAgranulocytosisAplastic anemiaLeukopenia Thrombocytopenia.TeratogenicityPhenytoin is a known teratogen and causes "fetal hydantoin syndrome"The syndrome consists of craniofacial anomalies \ broad nasal bridge, cleft lip and palate, microcephaly) and a mild form of mental retardation (average IQ=71)DermatologicHypertrichosisRashExfoliative dermatitisPruritisHirsutismCoarsening of facial featuresSJS and TENOthersGingival hypertrophy (overgrowth of the gums) (can be decreased with folate supplementation)Induction of reversible IgA deficiencyDrug-induced lupus.Hypocalcemia