Hydrocodone also known as dihydrocodeinone, belongs to a group of drugs called opioids often referred to as narcotics. It relieves pain by binding to certain receptors in the central nervous system mostly the μ-opioid receptor also known as MOR.
Hydrocodone is a semi-synthetic opioid drug. It is synthesized from codeine, an opioid alkaloid found in poppy. Hydrocodone has the same effect on the body as the better known opioid morphine. Hydrocodone Opioids are a group of medications most commonly used to relieve moderate to severe pain, but can be used to treat a cough and diarrhea. It is considered as a potent analgesic medication and is the most commonly prescribed opioid in the USA. It is a narcotic analgesic, meaning it can be abused and cause addiction, but it is used in medicine as a pain-relieving substance despite its ability to cause addiction. Due to its abuse potential, hydrocodone is not considered legal in most European countries, but is still in use in U.S.
Hydrocodone stimulates the body in a way that induces tolerance, which means that higher doses are needed to produce the same effect. This leads to a continuous increase in doses, with withdrawal symptoms appearing any time the drug is discontinued, which is why prolonged use can lead to addiction.
Most common side effects of hydrocodone are constipation, nausea, vomiting, fatigue and dizziness, headache and sleepiness. Hydrocodone should be carefully used in combination with other medications, and it is always advised to refer to a medical supervision before taking any other drug. Special precautions are given to the combination of hydrocodone and drugs and substances that are considered as central nervous system depressants such as benzodiazepines and alcohol. Antidepressants are also among drugs that are not recommended to be used with hydrocodone as they can lead to serotonin syndrome, a life-threatening condition. Drugs that inhibit CYP3A4 can increase blood levels of hydrocodone causing an increase in adverse effects and possible overdose. Therefore, it is contraindicated to use alcohol, other opioids, anti-anxiety drugs, anti-psychotics, central nervous system depressants and antihistamines with hydrocodone.
Even a single dose of hydrocodone can cause fatal respiratory depression which leads to coma and death. Therefore it is important not to use the drug in any way other than prescribed by your physician.
Hydrocodone is often mixed with other painkillers to produce different drug formulations for oral administration such as:
- Hydrocodone and Paracetamol (Vicodin, Lortab, Lorcet, Maxidone, Norco, Zydone)
- Hydrocodone and Ibuprofen (Vicoprofen, Ibudone, Reprexain)
- Hydrocodone and Aspirin (Alor 5/500, Azdone, Damason-P, Lortab ASA, Panasal 5/500)
- Controlled release hydrocodone (Hysingla ER, Zohydro ER)
Hydrocodone is placed in pregnancy category C of FDA meaning that its effect on a newborn is not yet tested enough. Infants whose mothers used hydrocodone regularly during pregnancy will express physical dependence and withdrawal syndrome when born. Some studies indicate that using opioids in early pregnancy increases chances of congenital disabilities.
Origin of Hydrocodone use
Hydrocodone was derived from codeine in the early 1920’s in Germany, with the idea to preserve analgesic potency and reduce some serious side effects of codeine. The thought was to produce an opioid drug that would aid in the treatment of moderate to severe pain, but without a high incidence of respiratory depression and addiction such as seen in codeine use. Despite fears that it could carry a high risk of dependency due to its euphoria-producing effect, it was approved for sale in USA and Canada in 1934. It was never as common in Europe as it was in the USA. Germany was the only European country that had significant use of hydrocodone until the manufacturing of the drug was discontinued due to its abuse, addiction and misuse potential. Today 99% of hydrocodone is prescribed and used in the USA, with only 1% covering the rest of the world.
How Hydrocodone is consumed
Hydrocodone is only available in an oral form, usually as tablets. The effects of hydrocodone begin within 10 to 20 minutes after administration with peak blood concentration within 30 to 60 minutes. It is not advised to use hydrocodone in any way other than orally because it can increase the chances of addiction. Hydrocodone is one of the most commonly abused drugs, and addicts tend to crush and snort or try to inject pills in an attempt to get more immediate effects. This carries significant health risks and can have important implications on health, leading to an increase in adverse effects and in some cases to overdose.
Effects of Hydrocodone
Short Term Use Effects
Hydrocodone strongly binds to μ-opioid receptor also known as MOR, but can also bind, although with less affinity, to the δ-opioid receptors or DOR. These receptors are targets for other opioid drugs such as morphine. By binding to MOR and DOR hydrocodone activates these receptors, which induces short-term effects on the body and central nervous system including analgesia, sedation, euphoria, nausea and decrease in blood pressure and respiration. Hydrocodone changes people’s perception of pain, which is considered as a desirable short-term effect, next to the feeling of numbness and euphoria. Unfortunately, these properties are considered as the main cause hydrocodone is so often abused.
Long Term Use Effects
Frequent and repeated use of hydrocodone leads to developing a tolerance to a drug meaning that higher doses are needed to achieve the same effect. This stimulates drug seeking behavior and may result in psychological and physical dependence. Even under physicians control the possibility of developing an addiction is not excluded. Chronic effects of hydrocodone on a body include:
- developing an addiction
- difficulties with job performance
- emotional lability and changes in personality
- liver failure
- impaired mental abilities
- respiratory depression
- adrenal insufficiency