Recommendations for malaria prophylactics should be individualised whenever possible. Many factors significantly influence the choice of malaria prophylactics.
These include:

Duration of stay within the area

Certain medicines cannot be used long-term due to an increase in the risk of adverse effects.

If you are going to a malaria area for longer than 2 weeks and will not be able to get suitable medical treatment, it may be necessary to take "back-up" treatment with you. (Discuss with your doctor).

Prevalence of mosquitoes

during dry seasons and at high altitudes, the risk of malaria is lower since the number of malaria- carrying mosquitoes is reduced.

The availability of malaria prophylactics

Your health status

Some medicines should not be taken under certain medical conditions.

Pregnant women should not enter malaria areas as they are at high risk of getting malaria. If they do go, however, they must either take chloroquine alone (in chloroquine-sensitive areas) or in combination with proguanil (in chloroquine-resistant areas). Although it is usually prudent for pregnant women to avoid taking medicine, in this instance, the risk of getting malaria far outweighs the possible adverse effects of the above drugs.

Degree of resistance of the malarial parasite

Where chloroquine resistance is high, additional or alternative medicines to chloroquine are necessary.