Morphine has truly stood the test of time. Few medicines can claim such a lengthy tenure in the world of medicine. Morphine fundamentally changed the way we approach pain management. Everyone feels pain differently, depending on many factors — from genetics to personal experience. Morphine created a benchmark from which pain management and treatment can branch out from.

Ironically, morphine was, at first, the stepping stone to the creation of other painkillers, yet now it has become a stepping stone to painkiller misuse. This issue of transitioning to other opioids from morphine can be traced back to tolerances, which develop when someone continuously uses a drug. The half-life of morphine is tied to tolerance because the shorter the half-life, the more of the drug a person may be tempted to take to treat their symptoms continuously. The more morphine is taken, the more likely that person is to develop a tolerance to the drug.

Chemically speaking, morphine only lasts a short amount of time in the body. After a few hours, the pain returns and if the individual has been taking the drug for months, withdrawal symptoms may also begin to develop. This difficulty often results in the continued use of the drug to alleviate the pain, which gradually requires larger doses than previously. The half-life of morphine is responsible for the length of time that the drug stays in a person’s system.

Morphine Half Life

Half-life refers to the amount of time it takes for the concentration of a drug in the body to reach 50 percent. The half-life provides physicians with a way to determine when a drug is most effective, as well as a time frame for when it will leave the body entirely. The shorter the half-life, the sooner another dose of the drug is necessary and the sooner the body adapts to the drug. Different types of morphine have different half-lives.

Half Life of Morphine Sulfate

Morphine comes in several forms and formulations including oral, extended release, intramuscular, subcutaneous, rectal, epidural and IV. Morphine sulfate is one such variety. The sulfate component, a chemical salt, makes morphine more soluble in water and easier for the body to absorb outright. This iteration is most notably available as tablets of five varying strengths: 15 mg, 30 mg, 60 mg, 100 mg and 200 mg. Each comes in a distinctive color to aid in distinction.

The half-life of morphine sulfate is anywhere between two and four hours. Patients who are taking lower doses, such as 15 mg, will have to take an additional pill or two throughout the day.

Morphine Half Life IV

When some people think of morphine, they picture an IV drip in a hospital setting, as this is one of the most widely used variants of the drug. Morphine IVs place the medicine directly into veins or muscles using sterilized needles. Though this method often occurs under medical supervision only — meaning a patient cannot conveniently self-medicate at home — it is thought to be a safer and more manageable approach due to the medical supervision that is present at a hospital or treatment facility.

Morphine’s half-life after the intravenous application is even shorter than that of oral use. The half-life is 90 to 180 minutes for IV morphine.

Morphine Half Life Calculator

A drug’s half-life calculation can be done by hand. The equation requires an understanding and accurate measurements of the body’s elimination rate of morphine, in addition to the rate of morphine in the body separate from the rate in the blood. To avoid doing the calculations by hand, some online tools exist for calculating the half-lives of drugs. Searching online for “morphine half-life calculator” reveals several half-life calculators for different drugs. These calculators can compute half-lives automatically. You can use these tools to get an estimate of morphine’s half-life related to any dosage amount taken. Always consult with your doctor before taking any new medication or altering an existing prescription in any way.

If you or someone you know needs help for a morphine addiction call The Recovery Village at 855.832.4308 to speak with a representative who can help.

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Editor – Thomas Christiansen
With over a decade of content experience, Tom produces and edits research articles, news and blog posts produced for Advanced Recovery Systems. Read more
Medical Disclaimer

The Recovery Village aims to improve the quality of life for people struggling with substance use or mental health disorder with fact-based content about the nature of behavioral health conditions, treatment options and their related outcomes. We publish material that is researched, cited, edited and reviewed by licensed medical professionals. The information we provide is not intended to be a substitute for professional medical advice, diagnosis or treatment. It should not be used in place of the advice of your physician or other qualified healthcare providers.