What are tramadol and codeine?
Tramadol and codeine are both opiates. Codeine is made from the poppy plant, just like morphine, heroin, and opium. Tramadol is chemically similar to codeine, but it’s synthesized from precursor molecules in a lab. Many doctors like it because it has a lower potential for addiction than other opioids, though that doesn’t mean it’s non-addictive.
Opiates work because the central nervous system has three main opioid receptors in the nerve cells that, when coupled with natural opioids your body makes, govern pain sensation, reward, aspects of gastrointestinal function, aspects of respiratory function, and aspects of urogenital function. These receptors are named after Greek letters: Mu receptors, Delta receptors, and Kappa receptors. They sit on the membrane of nerve cells and activate when an opioid — whether naturally occurring in the body or introduced in the form of a drug — fits into the molecule like a key in a lock.
Opiate drugs mimic the natural opioids produced by the body. Their molecules fit into the same receptors and activate them. Codeine, tramadol, morphine, and all other poppy derivatives target and activate mostly the Mu receptors, meaning they are “Mu receptor agonists.”
These receptors and the naturally occurring (endogenous) opioids they pair with are responsible for the body’s own efforts to deaden pain. Because of this, flooding the Mu receptors with pharmaceutical opioids like codeine, tramadol, and others can increase the painkilling (analgesic) properties of that part of the central nervous system.
Unfortunately, because the endogenous opioid system also governs reward pathways, pharmaceutical opioids are highly addictive. Endorphins are the main endogenous opioids your nervous system secretes in response to sex, a delicious meal, and other forms of pleasure. Because opiate drugs activate the same Mu receptors endorphins do, euphoria and a profound sense of well-being are potential side effects of all the opiate drugs on the market. Patients can become addicted physically and mentally as both their bodies and minds begin to crave that state of bliss.
Tramadol and codeine are much less potent than other opiates like morphine, heroin, and its synthetic counterpart Fentanyl. Because of this, short-term use of tramadol and codeine for cough or moderate pain symptoms comes with a relatively low risk of addiction or withdrawal.
The endogenous opioid system, as mentioned before, helps govern the muscle reflex that expands and contracts your ribcage to breathe in and out in response to carbon dioxide levels in the blood. Because opiate drugs suppress this respiratory response, small doses of drugs like codeine can help suppress coughing and reduce the pain of a sore throat in all sorts of diseases and conditions in which coughing and throat pain are symptoms. However, though researchers understand the cough reflex is associated with the endogenous opioid system, they haven’t figured out the exact mechanism by which codeine suppresses coughs. They don’t know why, for instance, it doesn’t work for some chronic coughs.