Chloroquine phosphate is the combination of chloroquine and phosphate, which has betterstability or water solubility. Atpresent, itisbelievedthat Chloroquine phosphate maymake the the glycosylation of virus receptor (ACE-2 on the surface of alveolarepithelialcells) insufficinet, prevent the virus frominvadinghumancells, and affect the early stage of virus replication, so as to play an antiviral role. 

The treatment plan with Chloroquine phosphate as follows: 

Adultsaged 18-65 yearsold; body weight:>50kg; (500mg per time; twice a day for 7 days);

Adultsaged 18-65 yearsold;bodyweight:<50kg;(500mg per time,twice a day for the first and second days;500mg per time, once a day for the third to seventhdays).

Side-effects:

1.According to the report of Wuhan Institute of Virology,ChineseAcademy of Sciences, the lethal dose of Chloroquine phosphate in adultsis 2-4g, whichis acute. According to reports, when the dosage of Chloroquine phosphate is >20mg/kg/day, itcan cause cardiactoxicity, and when the dosage is >30mg/kg/day, itcan cause cardiacarrest, whichisalso the mostserious adverse reaction of chloroquine phosphate. The seventh Edition of the diagnosis and treatment plan emphasizesthat Chloroquine Phosphate isforbidden in patients withheartdisease. 

2. The common adverse reactionsincludeabdominall pain, diarrhea, tinnitus, dizziness, headache, eyesight, anorexia, etc. The generalsymptoms are mild, and candisappearafterstopping the medicine. 

3.Eyediseases are the most important adverse reactions of Chloroquine phosphate, most are irreversible, mainlymanifested as mildretinaledema and pigment aggregation, dark spots and visualimpairment. And the tardive retinopathymayoccuryearslaterafterdrugwithdrawal. 

4. The long-term use of chloroquine phosphate may cause irreversiblehearingloss, and the large use of Chloroquine phosphate in pregnantwomenmay cause congenitaldeafness in children.

5. The half-life of Chloroquine phosphate is 2.5-10 days. Long-term use of Chloroquine phosphate cangraduallyincrease the blood concentration and the risk of cardiactoxicity. It isstillnecessary to pay attention to its adverse reactions for a long time afterdrugwithdrawal. 

The following points shouldbepaid attention to in clinical use of Chloroquine phosphate:

1. The blood routine shouldbemonitoredeveryotherdayduring the medicationperiod, such as progressive decrease of white bloodcells, progressive aggravation of anemia and thrombocytopenia, thenreduce or stop the medication, and closely monitor the blood routine.

2. ECG examinationshouldbedonebeforetreatment. ECG shouldbemonitored on the 5th and 10th day of treatment. Attention shouldbepaid to QT interval, such as QT interval prolongation or heart rate slowing down. Attention shouldbepaid to reduction or drugwithdrawal.

3. During the treatment, the patients wereasked about the changes of vision. Attention shouldbepaid to reduction or drugwithdrawal If the patients occuredwithhypopsia.

4.During the treatment, observe the mental state of patients, such as mental disorder or depression. Attention shouldbepaid to reduction or drugwithdrawal.

Drug combinationprohibited:

1. Cardiovasculardrugs: digitalisdrugs (digoxin, deacetylatedhairoside, digitalis glycoside, Physalis K), anti-arrhythmicdrugs(Class IA—-Quinidine, Procainamide, Class III—–Amiodarone, sotalol,ibutilide, dronedarone), Benpredil, Hydrochlorothiazide, Indapamide.

2. Anti-bacterials: Quinolones (Moxifloxacin, Levofloxacin), Macrolides (Erythromycin, Clarithromycin, Azithromycin), Triazoles (Fluconazole, Fluconazole, Itraconazole, Posaconazole), Penicillamine, Streptomycin.

3. Central nervousSystomdrugs: Methadone, Tricyclicantidepressants (Amitriptyline, Imipramine, Doxepin, Clomipramine, Melitracen), Citalopram, Anti-psychotics (Droperidol,Haloperidol, Chlorpromazine), Monoamine Oxidaseinhibitors(Phenylethylhydrazine, Isoniazid, Isocarbohydrazide, Selegilan, Anti-phenylcyclopropylamine, Moclobemide, Paglin).

4. GastronintestinalDrugs: Gastricmotilitydrugs (Domperidone, Cisapride), Antiemeticdrugs (Ondansetron, Dorasetron).

5. Others: Botethasone, Prednisolone, Heparin, Astemizole, Ammonium Chloride, Apomorphine, Octreotide, Terfenadine, Arsenic Trioxide.

Weshouldalsobeawarethatthere are many adverse reactions of Chloroquine phosphate. Cardiotoxicity and neurotoxicity are related to dose, and ophthalmototoxicity and ototoxicity are related to course of treatment. For light patients and ordinary patients, the advantages and disadvantages of usingshouldbestrictlyweighted. It shouldbenotedthat the drugtreatmentwindowisnarrow and overdose isverydangerous. Atpresent, thereis no specificblood concentration monitoring method and specific antidote. In addition to itswide tissue distribution, hemodialysis and hemoperfusion have no effect on Chloroquine phosphate poisoning.

For severe patients, taboosshouldbecarefullyexcluded, and at the same time, whether the basic diseases and organfunctioncanmeet the use requirements of the drugshouldbeconsidered. It issuggestedthat Chloroquine phosphate shouldbeusedunder the guidance of an experiencedspecialist , and the dosage and course of treatmentshouldbewellcontrolled. 

Annexe 5