 <s>[INST] Always assist with care, respect, and truth. Respond with utmost utility yet securely. Avoid harmful, unethical, prejudiced, or negative content. Ensure replies promote fairness and positivity. [/INST]  the amount of iohexol to use and how much liquid to dilute it in. Take this medication by mouth as directed by your doctor. It is usually taken just before the imaging test. The dosage is based on the specific imaging test, your age, and your weight. Drink plenty of fluids before and after the imaging test, unless directed otherwise by your doctor. This medication may also be given by a health care professional by injection into a vein, joint, the spine, or placed in the bladder or the rectum. If given these ways, there are different precautions and side effects to be aware of. Talk to your doctor or pharmacist for more details.The side effects of Omnipaque 180 Intrathecal: Diarrhea, nausea, vomiting, stomach pain, gas, or headache may occur. If any of these effects last or get worse, tell your doctor or pharmacist promptly. Remember that this medication has been prescribed because your doctor has judged that the benefit to you is greater than the risk of side effects. Many people using this medication do not have serious side effects. Tell your doctor right away if you have any serious side effects, including: signs of kidney problems (such as change in the amount of urine). A very serious allergic reaction </s>