I have not found a reliable remedy against hiccups – and I've tried a few, spanning from detraction to drinking water with head upside down. However, there are some household remedies that do work like a miracle, working snake oil, so to speak, here is my list of four:
• Sneezing – this is probably well known: gently press your nose with index finger & thumb and stroke down; sneezing need gone. Must be some inhibitory reflex. Always works.
• Stung by wasp or bee? This can be horrible, especially when in nature with children. The miracle cure: Always bring along an onion. In emergency, cut it in two, press and let the onion juice drop on the skin were stung. Needs only a drop or two. Don't know why this works.
• Speaking of onions: Tears when cutting up onions? The surprising cure: Swallow a bit of water and keep in in your mouth. Possibly the active substance is hygroscopic and prefers the water, rather than stimulating your mucosa.
• Wasps flying around your cake (especially in late summer, when the poor things are starving to death)? Magic move: place copper coins on the table. This latter one has not been tested fully to my satisfaction, but the one time I tried, it worked. Will have to experiment on that – does it really work, and why.