There are several choices for antimalarials. Consult with your doctor and discuss side effects of each related to diving (specifically Mefloquine and its side effects that are similar to decompression illness symptoms). Also ask about vaccinations. Make sure your
tetanus is up to date.
Typhoid and
Hepatitis A and
B vaccinations should be discussed.
Some of these drugs should not be taken by children or pregnant women
There is plenty of Malaria in Indonesia. Consult with your dive operator as to the risk in your area and what their experience has been.
The US Gov't CDC web site is an excellent resource
Chapter 4 - Malaria - Yellow Book | CDC Travelers' Health
CDC - Malaria
About Anti-malarial drugs
Diseases: Malaria: Prescription Drugs, Public Info | CDC Travelers' Health
Antimalarial Drug Information
Travelers to areas with malaria risk in Africa, South America, the Indian Subcontinent, Tajikistan,
Asia, and the South Pacific should take one of the following antimalarial drugs (listed alphabetically):
* atovaquone/proguanil (brand name is Malarone)
* doxycycline (one of the tetracyclines, not good for young children, increases sensitivity to the sun
* mefloquine (the brand name is Lariam - side effects may mimic decompression illness)
* primaquine (in special circumstances).
Note: Chloroquine is
NOT an effective antimalarial drug in Indonesia and should not be taken to prevent malaria in this region.
For general information on health for the traveler to Indonesia and vaccine recommendations
Health Information for Indonesia | CDC Travelers' Health
Also consider an overall longer trip (e.g some fly via Manado and spend time at Lembeh Straits or in Bali if you are coming that way). Depending on where you start just getting to/from Manado is 36 to 48 hours plus you will most likely have an overnight , check the schedule and then the flight to Sorong. You could spend almost six days traveling. You also might want to try to arrive a day in advance in Sorong just in case there is a problem with your flight.Either way, it will provide you with a rest day so you are fresh when you do your actual diving. Consult your dive operation for their recommendations.