Quinine Doxycycline

Malaria is transmitted from person to person by a certain species of the Anopheles mosquito. The four different protozoans causing malaria are Plasmodium falciparum, P. malariae, P. ovale, and P. vivax. Drugp used to treat or prevent malaria are called anti malarial drags. Three antimalarial drugs are discussed in the chapter chloroquine, doxycycline, and quinine sulfate. Other examples of antimalarial drugs in use today are listed in the Summary Drug Table Antimalarial Drugs. 

Chloroquine (Aralen) is also used in die treatment of extraintestinal amebiasis (see section on Amebicides). Doxycycline is also used to treat infections caused by Neisseria gonorrhoeae, Treponema pallidum, Listeria monocytogenes, Clostridium, and Bacillus anthracis when penicillin is contraindicated. Quinine also may be used for die prevention and treatment of nocturnal leg cramps. 

Drugs that may interact with rifabutin include the following Anticoagulants, azole antifungal agents, benzodiazepines, beta blockers, buspirone, corticosteroids, cyclosporine, delavirdine, doxycycline, hydantoins, indinavir, rifamycins, losartan, macrolide antibiotics, methadone, morphine, nelfinavir, quinine, quinidine, theophylline, aminophylline, tricyclic antidepressants, and zolpidem. 

Doxycycline Tetracycline Treatment (with quinine) of infections with P falciparum chemoprophylaxis... 

Quinine sulfate is appropriate first-line therapy for uncomplicated falciparum malaria except when the infection was transmitted in an area without documented chloroquine-resistant malaria. Quinine is commonly used with a second drug (most often doxycycline or, in children, clindamycin) to shorten quinine s duration of use (usually to 3 days) and limit toxicity. Quinine is less effective than chloroquine against other human malarias and is more toxic. Therefore, it is not used to treat infections with these parasites. 

Clindamycin (see Chapter 44) is slowly active against erythrocytic schizonts and can be used after treatment courses of quinine, quinidine, or artesunate in those for whom doxycycline is not recommended, such as children and pregnant women. Azithromycin (see Chapter 44) also has antimalarial activity and is now under study as an alternative chemoprophylactic drug. Antimalarial activity of fluoroquinolones has been demonstrated, but efficacy for the therapy or chemoprophylaxis of malaria has been suboptimal. 

Chloroquine-resistant Quinine Artemisinin derivatives Atovaquone-proguanil Mefloquine Pyrimethamine-sulfadoxine Antibacterials (e.g., clindamycin, doxycycline, sulfamethoxazole, or tetracycline] ... 

Bind to other drugs that are administered within 1 or 2 hours of the antacid, This process results in reduced availability of the co-administered drug for absorption, For example, the chelation of tetracyclines (e.g, tetracycline, doxycycline) will decrease their absorption by up to 90%, Avery similar process - precipitation - occurs with drugs such as quinine with aluminium and magnesium hydroxide preparations, which results in a decreased absorption of quinine, It has to be noted that the absorption of fluoroquinolones (e g. ciprofloxacin, norfloxacin, ofloxacin, enoxacin, perfloxacin i will be decreased by 60-75% if they are co-administered with divalent and trivalent cations. Patients are recommended not to take these divalent and trivalent cationic preparations until fluoroquinolone therapy is discontinued. 

Acebutolol, amiloride, amiodarone, benzthiazide, broxaldine, broxyquinoline, cinchophen, clefamide, clemastine (green rim), cyclopenthiazide, diphenadione, doxycycline, enoxolone, fenbufen, frusemide, halquinol, hydroquinidine, hydroquinine, lorazepam, methyl benzoquate, 5-methyltryptamine, a-methyl-tryptamine, iV-methyltryptamine, metolazone, minocycline, piperacetazine (- red), procyclidine, quinidine, quinine, rimiterol, salbutamol, salinazid, sodium cromoglycate, trichlormethiazide, veratrine (— violet), zomepirac... 

A quinine satf 600 mg 8-hourly by mouth for 7 days followed by pyrimethamine plus sulfadoxine (Fansidar) 3 tablets as a single dose. Where there is resistance to Fansidar, doxycycline 200 mg, should be given after the course of quinine daily for at least 7 days. This additional therapy is necessary as quinine alone tends to be associated with a higher rate of relapse. 

Fansidar or doxycycline should be given subsequently, as above (mefloquine is an alternative, but this must begin at least 12 hours after parenteral quinine has ceased). 

Drugs used to treat an acute attack. Blood schizonticides are used to suppress an acute attack, and the various drugs used include oral chloroquine, mefloquine or quinine plus pyrimethamine or doxycycline or halofantrine. 

Treatment quinine +/- either doxycycline or clindamycin or pyrimethamine... 

Clinical use The main use of quinine is in P falciparum infections resistant to chloroquine. Quinine is sometimes used with doxycycline to shorten the duration of therapy and limit toxicity. Quinidine, the dextrorotatory stereoisomer of quinine, is used intravenously in the USA for treatment of severe falciparum malaria. To delay emergence of resistance, the drugs should not be used routinely for prophylaxis. 

Quinine sulfate + doxycycline, or Tetracycline + Primaquine phosphate... 

Adverse effects. Adverse effects of quinine include abdominal pain, nausea, tinnitus, headache, blindne.ss and hypersen.siiiviiy reactions, icHu( uinc may cause neuropsychiatric reactions and Matarone or doxycycline are increasingly being used to provide prophylaxis in areas of chioroquinc-resistant P. falcipanim,... 

Doxycycline does not appear to alter the pharmacokinetics of quinine. Tetracycline increases quinine levels and has been found to improve efficacy. 

In a study in 13 patients with acute falciparum malaria, the addition of intravenous doxycycline to treatment with intravenous quinine did not affect quinine pharmacokinetics, when compared with 13 patients taking... 

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