Opioids are a broad classification of drugs that encompasses a wide variety of both licit and illicit substances. There are dozens of different types of opioids and opioid-derivatives and just as they vary in their purpose, so does the duration of how long they stay in the body. Just because you may no longer feel the effects of a drug doesn’t mean that it’s out of your system. Whether you use opioids to manage pain or to help with opioid withdrawal systems, understanding how long opioids stay in your system is crucial to doing so safely.
Types of Opioid Durations
Opioids are generally categorized into three timespans: long-acting, short-acting, and ultra-short-acting (which is also known as ‘rapid onset’). The difference between the durations is quite intentional: some opioids are meant to last a long time, others are not. Medical professionals will determine which opioid they prescribe based on the type of pain and the circumstances of it.
An opioid’s duration in the body however is not indicative of its strength. The shortest lasting opioid does not inherently mean it is weak, the longest acting doesn’t inherently make it the most potent. The unique combination of opioid duration and strength is very deliberately synthesized depending on the specific medical need. Below are a few examples of the different opioid duration classifications along with the opioids that fall into each category.
Ultra Short-Acting Opioids (Fentanyl, Remifentanil)
What is Drug Half-Life? Why Some Opioids Last Longer Than Others
Half-life is a pharmacology term at the core of determining how long an opioid – or any sort of drug for that matter – takes to leave the system. As its name implies, it refers to the amount of time it takes for half of the total amount of substance to be eliminated from the body. Medically, it’s most practical use is to help prevent drug toxicity, and is used in doctor prescribing practices in determining dosing schedules (how frequently you are to take a medication).
So here’s how it works: The half-life of opioids can range between 36 hours and a little over half an hour. This time period is determined by pharmacokinetic reactions and is only somewhat influenced by physiological or circumstantial factors of the individual. It typically takes 4 or 5 half-lives for a drug to be completely eliminated from the system, however, this is only if no more of the substance has been entered into the body.
Factors that affect how long opioids stay in your system
The factors that affect how long opioids stay in the system primarily fall into two categories: drug-related and physiological. An opioid’s half-life will be most strongly influenced by the drug’s purpose and potency, but can also be influenced by other factors to a certain degree. Other factors like one’s age, ethnicity, weight, etc. have a lesser effect but are still significant enough to be taken into account.
- Type of opioid
- Tolerance/Level of use
- Method of administration
- Presence of other drugs in the body
- Previous drug addiction
- Body mass
- Body fat
- Liver and kidney healthy
Why It Matters
One of the biggest causes of adverse opioid side effects is when other substances are added to the mix. These substances can be alcohol, illegal narcotics, prescription medications, or something as simple as a glass of grapefruit juice.
Accidental overdoses – another very real concern – is something that knowing how opioids are processed and broken down in the body can help prevent. From 2019 to 2010, the rate of opioid-related overdoses increased by nearly 40%, resulting in tens of thousands of deaths each year. Talk to your doctor about how long opioids stay in your system and what drug interactions to consider to avoid adverse effects.