Codeine (Oral)

As a narcotic analgesic, Codeine is used as a common painkiller that treats pain symptoms through suppression of pain messengers in the central nervous system.


Codeine can be a very beneficial medication to patients suffering from any number of painful disorders. It works like many other painkillers by suppression of pain messengers in the central nervous system, leading to quick relief for those suffering from both acute and chronic pain. However, when it is used for a long duration it has an extreme risk of becoming habit-forming and resulting in both mental and physical dependence on continued use even if the pain it was prescribed for is no longer present. Patients who are experiencing pain and require the relief that codeine will bring should not consider addiction a risk, as when properly used Codeine is a relatively safe narcotic to use for treating pain. However, use of this drug should be discontinued when pain is no longer experienced.

If symptoms of physical dependence and withdrawal are experienced when a patient stops taking Codeine, the drug may need to be continued in scaled smaller doses over a specific interval until it is stopped completely. As a narcotic substance, Codeine is only available by prescription for a specifically diagnosed condition and should be used with caution. When prescribed, it may be taken in a number of forms including a solution, syrup, tablet and an extended-release tablet depending on how it will best serve the condition it is treating. It is important to note that misuse or overuse of Codeine can result in addiction, overdose or even death.

Conditions Treated

  • Chronic Pain
  • Acute Pain

Type of Medicine

  • Opioid Painkiller

Side effects

One of the drawbacks of Codeine as a treatment for pain is that it comes with a high number of potential side effects for patients who are using it for the treatment of pain. Some of these side effects are serious enough to warrant medical attention, if the following symptoms occur immediate medical attention may be necessary:

  • Bloating
  • Blurred vision
  • Chills
  • Cold, clammy skin
  • Confusion
  • Constipation
  • Darkened urine
  • Difficult or troubled breathing
  • Dizziness
  • Dizziness, faintness, or lightheadedness when getting up suddenly from a lying or sitting position
  • Fainting
  • Fast, irregular, pounding or racing heartbeat/pulse
  • Fast, weak pulse
  • Feeling of warmth
  • Fever
  • Indigestion
  • Irregular, fast or slow, or shallow breathing
  • Lightheadedness
  • Loss of appetite
  • Nausea
  • Low blood pressure or pulse
  • Shallow breathing
  • Pains in the stomach, side, or abdomen, possibly radiating to the back
  • Pale or blue lips, fingernails, or skin
  • Redness of the face, neck, arms, and occasionally, upper chest
  • Shortness of breath
  • Stopping of the heart
  • Sweating
  • Unconsciousness
  • Unusual tiredness or weakness
  • Vomiting
  • ?Wheezing
  • ?Yellow eyes or skin

As a narcotic, Codeine comes with a significant change of overuse and/or overdose. If any of the following symptoms occur they may indicate that the patient is suffering from an overdose. Call for emergency medical assistance immediately if a patient has any of these symptoms of an overdose:

  • Bluish lips or skin
  • change in consciousness
  • chest pain or discomfort
  • constricted, pinpoint, or small pupils
  • decreased awareness or responsiveness
  • extreme sleepiness or unusual drowsiness
  • loss of consciousness
  • no blood pressure or pulse
  • severe sleepiness
  • slow or irregular heartbeat

Along with the serious side effects listed above, there may be some routine side effects of the medication that is not as serious. Codeine takes some time for the body to adjust to its dose and may have some temporary side effects while it undergoes this adjustment. These routine side effects may not necessarily require any medical attention. Under usual conditions, they will subside as the body gets used to the strength of the dose. If the symptoms seem more intense than normal, worsen with time, or do not get better after a brief interval a doctor should be consulted about them as they may indicate a more serious condition.

Some of the more common routine side effects include drowsiness and lethargy or uncontrollable relaxation. Codeine may cause temporary skin problems in some individual including hives or welts, itching skin, redness of the skin, and skin rash. It has also been known to cause problems with the digestive system, such as dry mouth, abdominal or stomach pain, cramps, diarrhea, and excessive weight loss. It has been associated with problems of perception including blurry vision, loss of vision, disturbed color perception, double vision, halos around lights, night blindness, tunnel vision and an overbright appearance of lights. Temporary mental or neurological conditions associated with beginning to take Codeine include a false or unusual sense of well-being, fear or nervousness, feeling of constant movement of self or surroundings, the sensation of spinning, sleeplessness, trouble sleeping or an inability to sleep at all. Some who take Codeine may experience sharp headaches or be unable to stop themselves from shaking.

While not all individuals will necessarily experience any of these side effects, medications such as Codeine can affect people differently depending on their level of tolerance. If side effects occur that are not listed or if any other symptoms are noticed, check with your doctor to ensure that this is not an indication of a more serious condition developing.


The dose of Codeine required for pain may be drastically different depending on many factors ranging from the weight of the patient to the severity of the pain or injury being treated. The medication is a controlled substance and is only to be used as directed by a doctor, so all doctor's orders in regards to the dosage should be followed. The dosage levels discussed here are only averages determined by the manufacturer and may not match what is the on the label of your prescription. Do not change doses based on these guidelines or how effective you feel the medication to be because serious consequences up to and including overdose and death can result from overuse.

The dosing regimen for Codeine may depend on the strength of the medication, its delivery method, and how frequent the doses are. In general, the duration between doses should be strictly observed even if the pain is being experienced between doses. Pain management balanced with responsible dosing practices is crucial when using narcotic medication.

The oral dosage in tablet form is used for mild to moderately severe pain and may be used by either adults or children. Adult patients will generally be prescribed between 15-60mg every four hours for the period of time it is needed. This dosing schedule should not exceed 360mg in a single day. While children may be prescribed the medication in this form, a pediatric specialist much determines the amount of the dose and its frequency.

In the event that a dose is missed, care must be taken in taking the next dose. If it has only been missed by a short amount of time it may be safe to take the missed dose. However, it is very important that the doses are not be taken too close together. It may be safer to wait until the next scheduled dose unless the pain becomes unbearable. In this case, the entire dosing schedule should be adjusted to maintain the amount of time between doses. Under no circumstances is Codeine to be taken as a double dose.


Codeine can have significant interactions with other drugs that are used for any number of conditions. Some of these drugs should never be used together because of the severity of these interactions while others can be mitigated by adjusting the dose or schedule of one or both medicines. Some medications may be so necessary to the patient's wellbeing that they may need to continue to be taken with Codeine as no other alternatives exist. In any case, the prescribing doctor should be fully aware of any and all drugs being taken at the same time that the patient is taking Codeine.

The use of Naltrexone is known to cause serious side effects and its use is not recommended. If at all possible, discontinue use of this medication or ask your doctor to find an alternative treatment.

Some of the drugs that are known to cause interactions with Codeine may not normally be recommended but may be required as a result of a lack of alternatives or the grave condition that they are a treatment for. While this list is not all-inclusive, it does contain those that have the most notable side effects.

  • Acepromazine
  • Alfentanil
  • Alprazolam
  • Amisulpride
  • Amobarbital
  • Anileridine
  • Aripiprazole
  • Asenapine
  • Baclofen
  • Benperidol
  • Bromazepam
  • Bromopride
  • Buprenorphine
  • Bupropion
  • Buspirone
  • Butabarbital
  • Butalbital
  • Butorphanol
  • Carbinoxamine
  • Cariprazine
  • Carisoprodol
  • Carphenazine
  • Chloral Hydrate
  • Chlordiazepoxide
  • Chlorpromazine
  • Chlorzoxazone
  • Clobazam
  • Clonazepam
  • Clorazepate
  • Codeine
  • Conivaptan
  • Cyclobenzaprine
  • Dantrolene
  • Darunavir
  • Dezocine
  • Diacetylmorphine
  • Diazepam
  • Dichloralphenazone
  • Difenoxin
  • Dihydrocodeine
  • Diphenhydramine
  • Diphenoxylate
  • Donepezil
  • Doxylamine
  • Droperidol
  • Enflurane
  • Estazolam
  • Eszopiclone
  • Ethchlorvynol
  • Ethopropazine
  • Ethylmorphine
  • Fentanyl
  • Flibanserin
  • Flunitrazepam
  • Fluphenazine
  • Flurazepam
  • Fospropofol
  • Halazepam
  • Haloperidol
  • Halothane
  • Hexobarbital
  • Hydrocodone
  • Hydromorphone
  • Hydroxyzine
  • Iloperidone
  • Isoflurane
  • Ketamine
  • Ketazolam
  • Ketobemidone
  • Levorphanol
  • Lorazepam
  • Lormetazepam
  • Lurasidone
  • Meclizine
  • Medazepam
  • Melperone
  • Meperidine
  • Mephenesin
  • Mephobarbital
  • Meprobamate
  • Meptazinol
  • Mesoridazine
  • Metaxalone
  • Methadone
  • Methdilazine
  • Methocarbamol
  • Methohexital
  • Methotrimeprazine
  • Methylene Blue
  • Midazolam
  • Molindone
  • Moricizine
  • Morphine
  • Morphine Sulfate Liposome
  • Nalbuphine
  • Nicomorphine
  • Nitrazepam
  • Nitrous Oxide
  • Olanzapine
  • Opium
  • Opium Alkaloids
  • Orphenadrine
  • Oxazepam
  • Oxycodone
  • Oxymorphone
  • Paliperidone
  • Papaveretum
  • Paregoric
  • Paroxetine
  • Pentazocine
  • Pentobarbital
  • Perampanel
  • Perazine
  • Periciazine
  • Perphenazine
  • Phenobarbital
  • Pimavanserin
  • Pimozide
  • Piperacetazine
  • Pipotiazine
  • Piritramide
  • Prazepam
  • Primidone
  • Prochlorperazine
  • Promazine
  • Promethazine
  • Propofol
  • Propoxyphene
  • Quazepam
  • Quetiapine
  • Ramelteon
  • Remifentanil
  • Remoxipride
  • Risperidone
  • Secobarbital
  • Sertindole
  • Sodium Oxybate
  • Sufentanil
  • Sulpiride
  • Suvorexant
  • Tapentadol
  • Temazepam
  • Thiethylperazine
  • Thiopental
  • Thiopropazate
  • Thioridazine
  • Thiothixene
  • Tilidine
  • Tizanidine
  • Tolonium Chloride
  • Topiramate
  • Tramadol
  • Triazolam
  • Trifluoperazine
  • Trifluperidol
  • Triflupromazine
  • Trimeprazine
  • Zaleplon
  • Ziprasidone
  • Zolpidem
  • Zopiclone
  • Zotepine

Other Interactions that a patient taking Codeine should be aware of include certain food or drink that should be avoided when using Codeine. The most important is that alcoholic beverages should not be consumed with Codeine. This can cause serious problems with the nervous system including total impairment of thinking and judgment. In serious cases, this can even result in unconsciousness, falling into a coma or death by respiratory or heart failure. Some long-acting formulations of Codeine may be rapidly released when mixed with even a small amount of alcohol and the resulting high blood levels of Codeine may be lethal.


When taking Codeine, progress in healing and recovery should be very closely monitored by a physician. The extent to which the patient recovers should indicate whether or not Codeine will continue to be necessary as a pain management solution. Additionally, care should be taken not to use this medication with other CNS depressants such as antihistamines, allergy medicine, or a host of other medicines that may be prescribed for pain management, as a sleep aid, or for anesthetic purposes. Keep your doctor fully appraised of all medications that are being taken.

As Codeine can be significantly habit-forming, do not use this medication in any way other than as directed. If you feel that the medication is not working do not increase the dose to increase the effect. If dizziness or lightheadedness is experienced when getting up suddenly, sitting back down or laying down for a time may help recover from this effect. Exercise extreme caution in driving or using machinery if you are unsure how the drug will affect you.

One major concern when using Codeine or any opioid over a long period is that it can cause severe constipation. This may be mitigated by the use of laxatives or increasing fluid intake, but do this only as directed by a doctor. Other remedies including medications may help to relieve this, so ask your doctor if normal remedies do not work.

In the event that you experience extreme fatigue, confusion, or have difficulty breathing you should contact your doctor immediately. Certain people have a high metabolism that rapidly absorbs the drug into their system at a higher rate than is safe, and suffer greater side effects than normal metabolizers. However, do not suddenly stop the medication without first checking with your doctor as you may need to be gradually given a reduced dose to safely stop using Codeine. This gradual process significantly reduces the chances of withdrawal symptoms, which may include stomach cramps, anxiety, fever, nausea, runny nose, sweating, tremors and trouble sleeping.

Pregnant and nursing women are strongly cautioned against using Codeine. Using it while pregnant can cause withdrawal symptoms in newborns and seriously impair the development of the child.

Do not take any medications while using Codeine unless you have cleared them with your doctor. Whether these drugs are prescription or over-the-counter they may still pose a potential interaction risk or make side effects worse. Make sure that your doctor is also aware of any of the following conditions you may have a history of or are currently suffering from including:

  • Addison's disease
  • Alcohol abuse
  • Breathing or lung problems
  • CNS depression
  • Drug dependence/addiction
  • Enlarged prostate
  • Hypothyroidism
  • Kyphoscoliosis
  • Mental illness
  • Problems with passing urine
  • Brain tumor
  • Head injuries
  • Increased pressure in your head
  • Breathing problems
  • Paralytic ileus
  • Respiratory depression
  • Hypotension
  • Pancreatitis
  • Seizures
  • Kidney disease
  • Liver disease
  • Stomach or digestion problems


It is especially important to keep any and all Codeine is a safe and secure location. It is a very commonly abused drug and should be kept locked up or otherwise secured in a closed container. The area where it is stored should be at room temperature and away from potentially damaging elements such as direct sunlight, excessive heat, moisture, and freezing temperatures. Codeine should be kept out of the reach of those who can be harmed by taking or consuming it such as children or pets. If this medication has been taken by anyone other than the person it is prescribed for, or the manner in which it is meant to be taken, poison control measures may need to be taken. If an overdose is suspected, call for emergency medical services. If the medication is no longer needed it should be disposed of immediately. Do not use this medication if it is past its expiration date listed on its label.


While Codeine is a very effective painkiller, that is deeply beneficial to patients who are suffering from pain that can only be treated through the administration of a painkiller, that doesn't change the risks that are associated with it as a narcotic. These risks can be significant when it is used for a long period of time, especially unmonitored. Along with its potential for abuse and overdose, it can potentially cause other undesirable effects with long-term use and may cause patients to not notice serious conditions that their pain may indicate. This is a drug that must be used only as prescribed and for the period of time that it is indicated for, this may require close monitoring on the physician's part. Communication between doctor and patient is essential in ensuring that this medication is not overprescribed or misused, especially once a condition has fully healed.

Before prescribing Codeine for pain, the doctor should be aware of all medical conditions that may preclude its use, including a rare allergy to the medication. This is especially true for breathing problems such as com/health/asthma-attack/">asthma attacks or hyperventilating, as taking Codeine with these locations can lead to slower breathing or death. When used correctly and not abused, Codeine may be a patient's best way to treat their painful condition, but both doctor and patient should sanction its use with both eyes open. There are significant risks that go with the benefits of pain management but it is a drug that should only be used in moderation and for a well-considered period of time.


Last Reviewed:
February 01, 2018
Last Updated:
April 04, 2018