5.4.1 Antimalarials

Malaria prophylaxis

• The Department of Health advises GPs that private prescription forms should be used to prescribe drugs for malaria prophylaxis. Chloroquine and proguanil are available 'over the counter' (OTC) whereas mefloquine and Malarone require a private prescription.
• Refer to BNF or MIMS for telephone numbers for up to date advice on recommended products.
• Costs of treatment can vary between community pharmacies. Advise patients to obtain information on cost of dispensing private prescriptions for malaria prophylaxis from their community pharmacy.
• Due to the risk of mixed falciparum and non-falciparum malarias treatment should be directed against falciparum malaria unless, due to geographical constraints or the results of diagnostic tests, one can be confident that infection is due purely to non-falciparum plasmodia.

Malaria treatment

Drugs used to treat malaria not listed here:

• Doxycycline, see 5.1.3 Tetracyclines

Riamet

(Artemether with lumefantrine)

• Tablets 20mg/120mg

Atovaquone with proguanil hydrochloride 

• Tablets 250mg/100mg
• Paediatric tablets 62.5mg/25mg

Chloroquine

• Tablets 250mg (equivalent to 155mg chloroquine base)
• Oral solution 80mg/5ml (equivalent to 50mg chloroquine base/5ml)

Notes

1. MHRA Drug Safety Update (February 2022): Hydroxychloroquine, chloroquine: increased risk of cardiovascular events when used with macrolide antibiotics; reminder of psychiatric reactions
   1. An observational study has shown that co-administration of azithromycin with hydroxychloroquine in patients with rheumatoid arthritis is associated with an increased risk of cardiovascular events (including angina or chest pain and heart failure) and cardiovascular mortality
   2. Carefully consider the benefits and risks before prescribing systemic azithromycin or other systemic macrolide antibiotics (erythromycin or clarithromycin) to patients being treated with hydroxychloroquine or chloroquine
   3. Be vigilant for psychiatric reactions associated with hydroxychloroquine or chloroquine, especially in the first month of treatment; events have been reported in patients with no prior history of psychiatric disorders
   4. See the safety update for advice to give to patients
      

Primaquine

• Tablets 7.5mg (unlicensed preparation)

Fansidar

(Pyrimethamine with sulfadoxine)

• Tablets 25mg/500mg

Quinine sulphate

• Tablets 200mg, 300mg

Notes

1. MHRA Drug Safety Update (December 2014):
   1. Quinine is not a routine treatment for nocturnal leg cramps, and should only be used when cramps regularly disrupt sleep
   2. Before use of quinine for nocturnal leg cramps, the risks should be carefully considered relative to the potential benefits
   3. After a trial of at least 4weeks, treatment should be stopped if there is no benefit. If treatment continues, the benefits should be assessed around every 3 months
   4. Patients should be warned not to exceed the recommended dose. Serious side effects including irreversible blindness and death may occur with overdose
   5. Thrombocytopenia is a rare but potentially life-threatening adverse reaction associated with quinine. Patients should be instructed to stop treatment and consult a physician if signs of thrombocytopenia occur, such as unexplained petechiae, bruising, or bleeding
2. MHRA Drug Safety Update (November 2017):
   1. Be aware of dose-dependent effects on the QT interval and use caution if prescribing quinine in patients:
      • with conditions that predispose to QT prolongation such as pre-existing cardiac disease or electrolyte disturbance
      • taking other medicines that could prolong the QT interval
      • with atrioventricular block
   2. Monitor patients closely if administration of quinine with phenobarbital or carbamazepine is necessary; serum levels of these anticonvulsant medicines could become raised and cause anticonvulsant toxicity
   3. Consult the Summary of Product Characteristics for a full list of interacting medicines and potential adverse reactions

Artesunate

• 60mg powder and solvent for solution for injection

Quinine dihydrochloride

• Injection 300mg/ml, 600mg/2ml (for infusion only) (unlicensed)

5.4.2 Amoebicides

Drugs used for amoebic infection not listed below:

• Metronidazole, see 5.1.11 Nitroimidazole derivatives

Diloxanide furoate

• Tablets 500mg

Notes

1. For use within University Hospitals Plymouth NHS Trust

5.4.8 Drugs for pneumocystis pneumonia

Pentamidine isetionate

• Injection 300mg
• Nebuliser solution 300mg

Atovaquone

• Oral suspension 750mg/5ml (226ml)