Do not take this medication with any of the following:
-Alcohol
-Antihistamines for allergy, cough, and cold
-Certain medications for anxiety or sleep
-Certain medications for depression, such as amitriptyline, fluoxetine, sertraline
-Certain medications for seizures, such as carbamazepine, phenobarbital, phenytoin, primidone
-General anesthetics, such as halothane, isoflurane, methoxyflurane, propofol
-Local anesthetics, such as lidocaine, pramoxine, tetracaine
-MAOIs, such as Carbex, Eldepryl, Marplan, Nardil, and Parnate
-Medications that relax muscles for surgery
-Other opioid medications for pain or cough
-Phenothiazines, such as chlorpromazine, mesoridazine, prochlorperazine, thioridazine
This medication may also interact with the following:
-Antiviral medications for HIV or AIDS
-Atropine
-Certain antibiotics, such as erythromycin and clarithromycin
-Certain medications for bladder problems, such as oxybutynin, tolterodine
-Certain medications for fungal infections, such as ketoconazole and itraconazole
-Certain medications for irregular heartbeat, such as amiodarone, propafenone, quinidine
-Certain medications for Parkinson disease, such as benztropine, trihexyphenidyl
-Certain medications for stomach problems, such as dicyclomine, hyoscyamine
-Certain medications for travel sickness, such as scopolamine
-Ipratropium
-Rifampin

They need to know if you have any of these conditions:
-Addison disease
-Brain tumor
-Frequently drink alcohol
-Gallbladder disease
-Head injury
-Heart disease
-History of substance use disorder
-Kidney disease
-Liver disease
-Low blood pressure
-Lung or breathing disease, such as asthma
-Mental health conditions
-Pancreatic disease
-Seizures
-Stomach or intestine problems
-Thyroid disease
-Trouble passing urine
-An allergic or unusual reaction to guaifenesin, codeine, other medications, foods, dyes, or preservatives
-Pregnant or trying to get pregnant
-Breastfeeding

You may develop tolerance to this medication if you take it for a long time. Tolerance means that you will get less symptom relief with time. Tell your care team if your symptoms do not start to get better or if they get worse.
Taking this medication with other substances that cause drowsiness, such as alcohol, benzodiazepines, or other opioids can cause serious side effects. Give your care team a list of all medications you use. They will tell you how much medication to take. Do not take more medication than directed. Call emergency services if you have problems breathing or staying awake.
Long term use of this medication may cause your brain and body to depend on it. This can happen even when used as directed by your care team. You and your care team will work together to determine how long you will need to take this medication. If your care team wants you to stop this medication, the dose will be slowly lowered over time to reduce the risk of side effects.
This medication may affect your coordination, reaction time, or judgment. Do not drive or operate machinery until you know how this medication affects you. Sit up or stand slowly to reduce the risk of dizzy or fainting spells. Drinking alcohol with this medication can increase the risk of these side effects.
This medication will cause constipation. If you do not have a bowel movement for 3 days, call your care team.
Your mouth may get dry. Chewing sugarless gum or sucking hard candy and drinking plenty of water may help. Contact your care team if the problem does not go away or is severe.
Talk to your care team if you may be pregnant. Prolonged use of this medication during pregnancy can cause temporary withdrawal in a newborn.
Talk to your care team before breastfeeding. Changes to your treatment plan may be needed. If you breastfeed while taking this medication, seek medical care right away if you notice the child has slow or noisy breathing, is unusually sleepy or not able to wake up, or is limp.
Long-term use of this medication may cause infertility. Talk to your care team if you are concerned about your fertility.

Keep out of the reach of children and pets. This medication can be abused. Keep it in a safe place to protect it from theft. Do not share it with anyone. It is only for you. Selling or giving away this medication is dangerous and against the law.
Store at room temperature between 15 and 30 degrees C (59 and 86 degrees F). Protect from light.
This medication may cause harm and death if taken by other adults, children, or pets. It is important to get rid of the medication as soon as you no longer need it or it is expired. You can do this in two ways:
-Take the medication to a medication take-back program. Check with your pharmacy or law enforcement to find a location.
-If you cannot return the medication, check the label or package insert to see if the medication should be thrown out in the garbage or flushed down the toilet. If you are not sure, ask your care team. If it is safe to put in the trash, take the medication out of the container. Mix the medication with cat litter, dirt, coffee grounds, or other unwanted substance. Seal the mixture in a bag or container. Put it in the trash.