SIDE EFFECTS: See also Warning section. Drowsiness, dizziness, headache, lightheadedness, blurred vision, upset stomach, nausea, constipation, or dry mouth may occur. If any of these effects persist or worsen, tell your doctor or pharmacist promptly. This medication can dry up and thicken mucus in your lungs, making it more difficult to breathe and clear your lungs. To help prevent this effect, drink plenty of fluids unless otherwise directed by your doctor. Remember that your doctor has prescribed this medication because he or she 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: involuntary behaviors/movements (e.g., fixed upward stare, neck twisting, tongue movements), mental/mood changes (e.g., hallucinations, confusion), ringing in the ears, shaking (tremors), trouble urinating, weakness. Get medical help right away if you have any very serious side effects, including: easy bruising/bleeding, slow heartbeat, persistent nausea/vomiting, severe abdominal pain, yellowing eyes/skin, seizure. Codeine is changed into a strong opioid drug (morphine) in your body. In some people, this change happens faster and more completely than usual, which increases the risk of very serious side effects. Get medical help right away if you notice any of the following: slow/shallow breathing, severe drowsiness/difficulty waking up, confusion. This medication may rarely cause a very serious condition called neuroleptic malignant syndrome (NMS). Get medical help right away if you have any of the following symptoms: fever, muscle stiffness/pain/tenderness/weakness, severe tiredness, severe confusion, sweating, fast/irregular heartbeat, dark urine, signs of kidney problems (such as change in the amount of urine). A very serious allergic reaction to this drug is rare. However, get medical help right away if you notice any symptoms of a serious allergic reaction, including: rash, itching/swelling (especially of the face/tongue/throat), severe dizziness, trouble breathing. This is not a complete list of possible side effects. If you notice other side effects not listed above, contact your doctor or pharmacist. In the US - Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088 or at www.fda.gov/medwatch. In Canada - Call your doctor for medical advice about side effects. You may report side effects to Health Canada at 1-866-234-2345.

PRECAUTIONS: See also Warning section. Before taking this medication, tell your doctor or pharmacist if you are allergic to any of its ingredients; or to opioid pain relievers (e.g., morphine); or if you have any other allergies. This product may contain inactive ingredients, which can cause allergic reactions or other problems. Talk to your pharmacist for more details. Before using this medication, tell your doctor or pharmacist your medical history, especially of: abdominal problems (e.g., chronic constipation, ileus, pancreatitis), gallbladder disease, adrenal gland problem (e.g., Addison's disease), blood/immune system problems (e.g., bone marrow depression), brain disorders (e.g., seizures, head injury, tumor, increased intracranial pressure), breathing problems (e.g., asthma, emphysema, sleep apnea), diabetes, glaucoma, heart problems (e.g., angina, irregular heartbeat), high blood pressure, liver disease, mental/mood problems (e.g., depression, psychosis), obesity, a certain spinal problem (kyphoscoliosis), stomach/intestinal problems (e.g., ulcers, blockage), thyroid disease, trouble urinating (e.g., due to enlarged prostate or urethral stricture), personal or family history of a substance use disorder (such as overuse of or addiction to drugs/alcohol). This drug may make you dizzy or drowsy. Alcohol or marijuana can make you more dizzy or drowsy. Do not drive, use machinery, or do anything that needs alertness until you can do it safely. Avoid alcoholic beverages. Talk to your doctor if you are using marijuana. To reduce dizziness and lightheadedness, get up slowly when rising from a sitting or lying position. This medication may make you more sensitive to the sun. Limit your time in the sun. Avoid tanning booths and sunlamps. Use sunscreen and wear protective clothing when outdoors. Tell your doctor right away if you get sunburned or have skin blisters/redness. This medication may contain sugar and/or alcohol. Caution is advised if you have diabetes, alcohol dependence, or liver disease. Ask your doctor or pharmacist about using this product safely. Older adults may be more sensitive to the side effects of this drug, especially confusion, dizziness, drowsiness, constipation, trouble urinating, and slow/shallow breathing. Confusion, dizziness, and drowsiness can increase the risk of falling. Before using this medication, women of childbearing age should talk with their doctor(s) about the risks and benefits. Tell your doctor if you are pregnant or if you plan to become pregnant. During pregnancy, this medication should be used only when clearly needed. It may slightly increase the risk of birth defects if used during the first two months of pregnancy. Also, using it for a long time or in high doses near the expected delivery date may harm the unborn baby. To lessen the risk, take the smallest effective dose for the shortest possible time. Tell the doctor right away if you notice any symptoms in your newborn baby such as slow/shallow breathing, irritability, abnormal/persistent crying, vomiting, or diarrhea. This medication passes into breast milk and may have undesirable effects on a nursing infant, such as unusual sleepiness, difficulty feeding, trouble breathing, or unusual limpness. Breast-feeding while using this drug is not recommended. Consult your doctor before breast-feeding.

DRUG INTERACTIONS: See also Warning section. Drug interactions may change how your medications work or increase your risk for serious side effects. This document does not contain all possible drug interactions. Keep a list of all the products you use (including prescription/nonprescription drugs and herbal products) and share it with your doctor and pharmacist. Do not start, stop, or change the dosage of any medicines without your doctor's approval. Some products that may interact with this drug include: antihistamines applied to the skin (such as diphenhydramine cream, ointment, spray), cimetidine, metoclopramide, naltrexone. The risk of serious side effects (such as slow/shallow breathing, severe drowsiness/dizziness) may be increased if this medication is taken with other products that may also cause drowsiness or breathing problems. Tell your doctor or pharmacist if you are taking other products such as other opioid pain or cough relievers (such as morphine, hydrocodone), alcohol, marijuana, drugs for sleep or anxiety (such as alprazolam, lorazepam, zolpidem), muscle relaxants (such as carisoprodol, cyclobenzaprine), or other antihistamines (such as cetirizine, diphenhydramine). Check the labels on all your medicines (such as allergy or cough-and-cold products) because they may contain ingredients that cause drowsiness. Ask your pharmacist about using those products safely. Other medications can affect the removal of codeine/promethazine from your body, which may affect how codeine/promethazine works. Examples include azole antifungals (such as ketoconazole), bupropion, fluoxetine, macrolide antibiotics (such as erythromycin), HIV medications (such as ritonavir), paroxetine, quinidine, rifamycins (such as rifabutin, rifampin), certain drugs used to treat seizures (such as carbamazepine, phenytoin), among others. This medication may interfere with certain laboratory tests (e.g., some pregnancy tests, blood sugar tests, amylase/lipase levels), possibly causing false test results. Make sure laboratory personnel and all your doctors know you use this drug.

OVERDOSE: If someone has overdosed and has serious symptoms such as passing out or trouble breathing, call 911. Otherwise, call a poison control center right away. US residents can call their local poison control center at 1-800-222-1222. Canada residents can call a provincial poison control center. Symptoms of overdose may include: confusion, cold/clammy skin, fast/slow/irregular heartbeat, slow/shallow breathing, seizures, fainting, coma.