The Stomach
The word for stomach is želudac. To express that your stomach hurts, use the construction boli me (it hurts me) followed by the subject želudac. When stating the cause of the pain, use the preposition zbog (because of) followed by the genitive case, such as zbog loše hrane (because of bad food).
| My stomach hurts because of bad food. | Boli me želudac zbog loše hrane. |
Nausea and Feeling Sick
The noun for nausea is mučnina. You can state you have nausea using the verb imati, which puts the noun into the accusative case (imam mučninu).
| I have nausea and I cannot eat. | Imam mučninu i ne mogu jesti. |
Alternatively, you can use the noun muka (sickness). This is very commonly used in the impersonal construction muka mi je (I feel sick), which uses the dative pronoun mi (to me). You can connect this to a trigger using the conjunction čim (as soon as).
| I feel sick as soon as I look at food. | Muka mi je čim pogledam hranu. |
Vomiting and Diarrhea
The verb for vomiting is povraćati. To express that someone is doing something "instead of" something else, use the phrase umjesto da.
| Instead of eating, he is vomiting. | Umjesto da jede, on povraća. |
Diarrhea is proljev. Just like with nausea, use imati to say that you have it. To list symptoms together, the preposition uz (along with / besides) takes the accusative case, as in uz mučninu.
| Along with nausea, the patient has severe diarrhea. | Uz mučninu, pacijent ima jak proljev. |
Food Poisoning and Cramps
Poisoning is otrovanje. The phrase for food poisoning is otrovanje hranom, which uses the instrumental case for the word food (hrana -> hranom).
| It is considered that this is food poisoning. | Smatra se da je to otrovanje hranom. |
A cramp is grč, but they are typically experienced in the plural: grčevi. After the verb imati, use the accusative plural form grčeve.
| I have strong cramps in my belly. | Imam jake grčeve u trbuhu. |
Dizziness, Contagion, and Digestion
Dizziness is vrtoglavica. To say you feel dizzy, use the verb osjećati (to feel) paired with the accusative noun: osjećati vrtoglavicu.
| If you feel dizziness, do not drive. | Ako osjećaš vrtoglavicu, nemoj voziti. |
A stomach bug is usually a virus (virus) that can be highly contagious (zarazan).
| This virus is very contagious, that's why you should be careful. | Ovaj virus je jako zarazan, zato pazi. |
Finally, when talking about how well your stomach is processing food overall, the general term for digestion is probava.
| He has bad digestion because of stress. | On ima lošu probavu zbog stresa. |