ABSTRACT The antimalarials, chloroquine, hydroxychloroquine, and quinacrine, are used primarily for malaria; but they can be beneficial for cutaneous lupus erythematosus (LE), polymorphous light eruption, solar urticaria, and porphyria cutanea tarda. Antimalarials bind to deoxyribonucleic acid (DNA) which prevents DNA and ribonucleic acid (RNA) polymerase reactions and DNA heat inactivation; and they inhibit the LE cell phenomenon, antinuclear antibody reactions, and suppress lymphocyte transformation. By competing with calcium ion, they stabilize membranes and have an anesthetic effect. Their anti-inflammatory potential is due to their inhibition of hydrolytic enzymes, stabilization of lysosomes, interference with prostaglandin synthesis, blocking of chemotaxis, and antagonism of histamine responses. The antimalarials have no sunscreening properties. The most common toxic effects are cutaneous pigmentation, nausea, vomiting, diarrhea, mild ileus, and cycloplegia. There has been a reluctance to use chloroquine and hydroxychloroquine because of the possibility of retinopathy. However, if the "safe" daily dose limit of chloroquine, 2 mg per pound of body weight, and of hydroxychloroquine, 3.5 mg per pound of body weight, is followed, the chance of retinopathy is slight. Quinacrine does not cause retinopathy, but it has more cutaneous side effects than the other two agents.
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ABSTRACT: From 1963 to the present, many reviews of antimalarials for use in dermatology have mentioned the special sensitivity of children to these drugs. Fatal reactions have been limited to accidental or intentional overdosage and two instances of IM injection. While 1 gm of chloroquine can produce fatal reaction in very young children, analysis of published and unpublished cases show that adults exhibit a similar sensitivity when compared on a mg/kg basis. This information should encourage a physician to use antimalarials where appropriate, but special precaution should be taken to prevent poisoning.Pediatric Dermatology 08/1983; 1(1):89-91. · 1.52 Impact Factor
Article: Antioxidant action of antimalarials.[Show abstract] [Hide abstract]
ABSTRACT: The effects of antimalarials, chloroquine and quinacrine, on the generation of reactive oxygen species were examined both in polymorphonuclear leucocytes and in the xanthine-xanthine oxidase system. Antimalarials showed inhibitory effects on the production of reactive oxygen species probably by affecting cell functions, such as membrane phospholipid methylation. It is suggested that antimalarial agents can work as antioxidants at the site of inflammation protecting against auto-oxidative tissue damage with resultant anti-inflammatory effects.Annals of the Rheumatic Diseases 04/1986; 45(3):244-8. DOI:10.1136/ard.45.3.244 · 9.27 Impact Factor
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ABSTRACT: This paper reviews the published material on adverse reactions to chloroquine (CQ) and amodiaquine (ADQ) as used for anti-malarial chemophrophylaxis. Dermatologic reactions, including pruritus and photosensitivity, appear to be rather common. Ophthalmologic reactions include difficulty in visual accommodation, corneal deposits, and retinopathy, the last a serious condition that is reversible in its early stage by drug withdrawal, and that generally will not occur with less than four years of weekly CQ use. Neuromyopathy is a rare and serious reaction that may develop idiosyncratically after a small cumulative dose; it, too, is reversible by drug withdrawal. Seizures, syndromes of involuntary movements, psychosis, and ototoxicity have been reported occasionally. Fatal toxic overdoses may occur, especially following accidental ingestion by children. ADQ should not be used for anti-malarial prophylaxis because of associated agranulocytosis. Rabies vaccine given intradermally is less effective for pre-exposure prophylaxis while the patient is taking CQ. Care should be taken when prescribing prophylactic CQ to patients with heart block. In spite of its adverse effects, however, CQ is generally an extremely safe drug. Cq prophylaxis is recommended for pregnant women in CQ-sensitive malarial areas.Canadian family physician Médecin de famille canadien 11/1987; 33:2644-9. · 1.40 Impact Factor