Pruritus drug-induced

Hypersensitivity is most frequently manifested by pruritus and skin rashes. Severe drug induced immune thrombocytopenia can occur. Hemolysis may occur in patients with G6PD deficiency. 

Diphenhydramine, like other antihistamines, is most often used to provide symptomatic relief of allergic symptoms caused by histamine release. The drug is also used as an antitussive, a nighttime sleep aid for the short-term treatment of insomnia, and as a preventive and treatment for motion sickness. Diphenhydramine may be useful in the treatment of parkinsonian syndrome in geriatric patients including drug-induced ex-trapyramidal reactions. Diphenhydramine has been used topically for the temporary relief of pruritus and pain associated with various skin conditions including minor burns, insect bites, and minor skin irritation. 

Onyeji CO, Ogunbona FA. Pharmacokinetic aspects of chloroquine-induced pruritus influence of dose and evidence for varied extent of metabolism of the drug. Eur J Pharm Sci 2001 13(2) 195-201. 

Intravenous nalbuphine 3 mg (n — 101) has been compared with intravenous propofol 20 mg (n = 90) in a double-blind, randomized study, to determine efficacy in the treatment of intrathecal morphine-induced pruritus after cesarean delivery 10 minutes after the drug was administered (6). Nalbuphine was significantly more effective, especially in cases of moderate but not severe pruritus. Adverse effects such as reduced analgesia and increased nausea, vomiting, sedation, and dizziness were not significantly different between the two groups. 

Pruritus, rashes, and urticaria have been reported. Rifampicin-induced rashes often resolve spontaneously, even without drug withdrawal, although in others they can be severe and can be accompanied by systemic symptoms, in some cases amounting to anaphylaxis (11). 

A mild jaundice, typically occurring early in therapy, may be seen in some patients receiving chlorpromazine. Pruritus is rare. The reaction probably is a manifestation of hypersensitivity, because eosinophilia and eosinophilic infiltration of the liver occur. For uninterrupted drug therapy in a patient with neuroleptic-induced jaundice, it probably is safest to use low doses of a potent, dissimilar agent. Hepatic dysfunction with other antipsychotic agents is uncommon. Clozapine can cause potentially severe ileus and sialorrhea. 

Non-sedating antihistamines generally suffice to control the symptoms (Cap et al. 1985). At night, higher than usual doses of these drugs or the potent sedating Hi-blocker hydroxyzine may be used in patients with severe pruritus (Breathnach et al. 1983). In co-operative patients, a low-pseudoallergen diet (Henz et al. 1997) can be tried for about 4-6 weeks since it occasionally induces remissions (own unpublished results). 

MANAGEMENT OF ADVERSE DRUG REACTIONS Administration of butorphanol, a partial agonist and antagonist of the mu receptor, was able to prevent morphine-induced pruritus without increasing effects of opiate withdrawal including nausea and vomiting [59 ]. 

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