world’s malaria is now chloroquine-resistant ‘CRM’. The chloro- quine analog hydroxychloroquine sulphate (marketed as ‘Plaque- nil’) is often required.
Interestingly, in the post-COVID world, chloroquine in either form has become especially hard to obtain either on script or over-the-counter. This has affected the rating of chloroquine in the RPA table. The availability of an off-licence form of chloro- quine phosphate as a fish tank additive compensates for this dif- ficulty to some extent.
Lethal Dosage
Quantities in excess of 5gm of chloroquine base will result in a lethal blood level of the drug. 250mg of chloroquine phosphate salt has ~150mg of active chloroquine base in each 250mg tablet. Anything in excess of 2 packets (40 x 250mg tablets) would be a reliable lethal dose.
Hydroxychloroquine, marketed as Plaquenil 200mg tablets, has less available base and is less toxic, but 12gm (or 60 x 200mg tablets) would be effective.
Administration
The drug is taken by mouth whereby it is rapidly and completely absorbed from the gut. Administration involves crushing 50 tab- lets and then dissolving them in 100ml of water. This method will lead to rapid absorption from the gut. Note, however, this small drink will be extremely bitter.
If there are significant concerns over the bitter taste of the drug, the tablets could be crushed into a powder and then repackaged into ‘00’ or ‘000’ gelatine capsules (See the previous Chapter on Cyanide).