Seasickness is one of the most common worries we hear before someone books a boat trip, and it is a fair one. If you have ever felt queasy on a ferry or a cruise, you want to know what you are getting into. The honest answer depends on where the boat goes much more than on the boat itself.
Why people get seasick
Motion sickness starts when your inner ear feels movement that your eyes do not see, or the other way around. On the open ocean a boat rises and falls with the swell, rolls from side to side and never fully settles. Your brain receives mixed signals, and some people answer with nausea, cold sweat, yawning, a headache or sudden tiredness. Heat, an empty or overly full stomach, strong smells and a short night of sleep make it worse. Some people never feel it; others feel it on a calm day.
The estuary: sheltered water, no ocean swell
The Tamarindo Estuary boat tour travels up the channels of a mangrove forest. Land and trees surround those channels, so there are no ocean waves rolling under the hull. What you feel is the soft motion of a boat moving along flat water and the pauses when the guide spots a crocodile resting on the mud or a heron in the roots. The boat is covered, which keeps you out of direct sun, and you stay seated for the whole tour of about two hours.
That is why the boat tour is open to all ages, from small children to grandparents. People who struggle on ocean boats usually find sheltered water much easier. Nobody can promise how every stomach will react, but calm water with land on both sides is about the gentlest setting a boat can offer.
The kayak tour uses the same protected channels. You sit close to the water, you set the pace with your own paddle and your eyes are always on the banks ahead, which is exactly what a sensitive stomach likes.
Sport fishing: this is the open Pacific
The half-day sport fishing trip is a different story. It goes out off the coast of Tamarindo, where the boat moves with the swell, and fishing usually includes stretches when the boat slows down or drifts while the lines are in the water. Slow rocking with no forward motion is the classic recipe for seasickness. It is the one tour in our catalog where our own list of things to bring includes motion-sickness pills if you need them. If the sea is not safe, the trip is rescheduled, but a safe sea can still have enough swell to bother a sensitive stomach.
Tips that help on any boat
- Look at the horizon. A fixed point far away tells your eyes what your inner ear already knows. Avoid reading or staring at your phone while the boat moves.
- Sit in the middle and low. The center of a boat moves the least. Ask the crew where the steadiest seat is.
- Stay in fresh air. Shade is good, a stuffy enclosed space is not. Keep your face out of engine fumes.
- Eat something light. Neither an empty stomach nor a heavy, greasy breakfast. Crackers, fruit or toast an hour or so before are a common choice.
- Drink water. Guanacaste is hot, and dehydration makes nausea worse. Sip regularly.
- Skip alcohol the night before and during the trip, and try to get a full night of sleep.
- Try ginger. Some people find that ginger candy or ginger tea settles the stomach. The research is mixed, but it is a mild option many travelers like.
- Keep busy. Holding a rod, chatting or scanning the water for birds keeps your mind off your stomach.
- Speak up early. If you start to feel unwell, tell the crew. Moving to a better seat or getting a breeze on your face helps far more at the first sign than later.
About medication
There are over-the-counter and prescription medicines for motion sickness. Many work better when taken some time before boarding, and some make people drowsy. The right choice depends on your health, your age and any other medicines you take, so ask a pharmacist or your doctor before the trip instead of improvising on the dock. We do not recommend any brand or dose.
Children and pregnancy
Children often handle calm water well, and the estuary boat tour is designed for every age. For an ocean trip, or before giving a child any motion-sickness product, talk to their pediatrician. If you are pregnant, check with your doctor before any boat outing, and especially before taking medication or heading out on the open sea.
Kayak, boat or fishing: how to choose
| Tour | Where | How it feels | Best for |
|---|---|---|---|
| Kayak | Sheltered estuary channels | Steady, at your own pace, close to the water | Active travelers 8 and up |
| Boat | Sheltered estuary channels | Gentle, seated, covered | All ages and sensitive stomachs |
| Sport fishing | Open Pacific off the coast | Swell, rocking, some drifting | Groups who want to fish and do not mind waves |
If your stomach is the main concern, start with the boat or the kayak; both stay in the protected channels of the mangrove. New to paddling? What to wear kayaking helps you get ready. If you still want to try the ocean, read sport fishing in Tamarindo for first-timers before you decide. Mixed group? Nothing stops you from booking the estuary for everyone and the fishing trip for the ones who want it.
Unsure about your own case? Write to us before you book, and we will tell you honestly which tour fits.
Updated November 10, 2026 · Written with the Conchita Tours guides.
Questions
Will I get seasick on the Tamarindo Estuary boat tour?
It is unlikely for most people. The tour runs through sheltered mangrove channels with no ocean swell, the boat is covered and you stay seated. Nobody can promise how every stomach reacts, but it is the calmest kind of water a boat can travel.
Is the kayak tour rough?
No. The kayak tour uses the same calm, protected channels of the estuary, and you set the pace yourself.
Should I take motion-sickness pills for sport fishing?
If you know you get seasick, ask a pharmacist or your doctor before the trip. Many products work better when taken ahead of time and some cause drowsiness, so do not improvise on the day.
What happens if the sea is rough on the day of my fishing trip?
If the sea conditions are not safe, the trip is rescheduled.
Can I go on a boat tour if I am pregnant?
Check with your doctor first, especially before taking any medication or going out on the open sea. The estuary boat tour is calm and seated, but your doctor knows your situation.
