 <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 cheeks in your mouth, occasionally switching sides of the mouth. You should finish the medication in 15 minutes to get the most relief. Do not bite or chew the medication. You may drink some water before using this medication, but do not eat or drink anything while you are using it. Avoid eating grapefruit or drinking grapefruit juice while using this medication unless your doctor or pharmacist says you may do so safely. Grapefruit can increase the chance of side effects with this medicine. Ask your doctor or pharmacist for more details. If you start to have side effects (such as dizziness, feeling sick to your stomach, severe drowsiness) before finishing a dose, your doctor may need to adjust your dose. Remove the rest of the lozenge from your mouth and store or dispose of it properly (see Medication Guide). Tell your doctor promptly if this happens. The dosage is based on your medical condition and response to treatment. If you need a second dose, wait 30 minutes after starting the first dose. Do not use more than 2 doses per episode of breakthrough pain. Wait at least 4 hours before using fentanyl lozenges again for another episode of breakthrough pain. To avoid any confusion and chance of overdose, you should only keep a supply of one strength </s>