Sorting out a box of memorabilia produced a dusty bottle full of crumbled brown pills:
The English part of the label:
Indication: Adequate and optimal treatment for gastrointestinal disorders, malnutrition, neurasthenia, tuberculosis, bere-beri, etc. It improves the appetite and promotes health
Dose: 4-8 tablets[,] 3 times a day
WAKAMOTO-HOMPO
EIYOTO-IKUJINO-KAI, CO., LTD.
SHIBA-PARK, TOKYO
My father spent several years on an all-expenses-paid trip to the South Pacific between 1943 and 1945. I have no idea what relation that bottle might have to his adventures, but the English text suggests it’s not a souvenir of those times.
Somewhat surprisingly, Wakamoto is still in business:
I’m sure it’s good for what ails you …
The Smell of Molten Projects in the Morning 
“It improves the appetite and promotes health”
Maybe stamina too? Aimo Koivunen’s “afterburner”.
Wikipedia (Aimo Koivunen)
have you tried google-translate – or similar – on the Japanese text on the label?
Maybe that will shed further light!
… fungus … nutrition … enzyme …
There’s surely meaning trapped inside, trying to claw its way out!
What’s the “Use By” date? Surely they were “responsible and ethical”enough and “concerned for patient welfare” to add one. Sigh. These days, it seems more closely linked to company financial health than that of the patient.
Hey, Wakamoto managed to get this far without that stuff, so why start now? After all, their contemporary pills have the same curative power!
If the bottle weren’t sealed so nicely, I’d be tempted to huff the contents. Probably fix whatever ails me with vintage-strength action.