Does Methadone Go Bad
In this brief article, we will be answering the question, “does methadone go bad?”, and will also be discussing the uses, side effects, dosage, and storage requirements of this medicine.
Does Methadone Go Bad?
Yes, all medications including methadone have an expiry date and may lose its effects with time. Medications that have passed their expiration date begin to lose their efficacy, and may not deliver the same effects as they did before.
The pharmaceutical product shelf life, also referred to as the expiration date, is the time period during which the product is expected to retain its identity, purity, quality, and strength when properly stored as specified in the container label.
However, the performance of the drug product beyond the manufacturer set shelf life has been a subject of study over the past several decades. Studies have shown that many drug products retain their shelf life quality characteristics such as potency and efficacy, several years beyond the expiration date if stored properly (1).
Nevertheless, the US Food and Drug Administration (FDA) recommends disposing of medications once they expire, and to consult a doctor for a fresh new supply.
Does Methadone Expire?
Yes, Methadone expires. All medications expire, because they are chemical compounds that degrade over time, as they are subjected to environmental conditions.
Degradation of medications is mostly caused by chemical reactions (eg, oxidation because of oxygen exposure, hydrolysis because of water exposure) and physical reactions (eg, alteration of particle size, disintegration of a suspension/emulsion, adsorption of water), both of which are temperature dependent (5). The shelf life of the medication is determined when the concentration of the active drug is decreased from 100% to 90%.
Therefore, the rate in which a drug degrades and loses its efficacy depends mainly on the nature of the drug and its storage conditions.
How Should You Store Methadone?
Methadone in the form of tablets should be stored at 20° to 25°C (68° to 77°F), with excursions permitted between 15° to 30°C (59° to 86°F). Protect from light. Store in carton until contents have been used (4).
Solutions of Methadone should be stored in the refrigerator for increased shelf life of at least 180 days, when stored in clear glass vials at 5°C (3).
What is the shelf life of Methadone?
The shelf life of Methadone varies, depending on the form it is prepared and the trademark of the commercial product. In the case of Methadone in form of 10 mg tablets, the shelf life for Methadone-ZN and Methadol Pharmascience is 5 years and for Methaddict and Methafin ІС is 3 years (2).
Methadone hydrochloride for injection diluted in saline solutions (at 1, 2, or 5 mg/mL) was reported to be stable for at least 4 weeks at room temperature. Solutions of methadone hydrochloride prepared in orange-flavored Tang® drink mix for oral administration were stable for 91 days at room temperature or under refrigeration methadone hydrochloride for injection (5 mg/mL) (3).
How to Identify if Methadone has Gone Bad?
To identify that Methadone has gone bad, it is necessary to be aware of signs of changes on the properties of the drug, such as color, odor and consistency. However, to identify an expired medication is not always easy, since not all drugs give evident signs of degradation or loss of efficacy (6).
Expired solubilized Methadone in the injection form is, on the other hand, simpler to identify. It loses its stability and precipitates.
What happens if You Take Expired Methadone?
When you take expired methadone or any other expired medication, you can experience the insufficient expected effect of the drug or even negative effects. There are a number of potential harms that can occur when an expired medication is ingested. There is a risk that degradation has occurred due to the action of time or that it may have degraded because it was not stored according to the recommendations.
In addition to having partially lost its effect, the degraded drug can cause unforeseen and unwanted side effects due to the effect of possible toxic compounds generated. Patients with serious and life-threatening illnesses can be particularly vulnerable to potential hazards from drugs that have undergone degradation.
In this brief article, we answered the question, “does methadone go bad?”, and also discussed the uses, side effects, dosage, and storage requirements of this medicine.
If you have any other questions or comments please let us know.
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Khan, Saeed R., et al. United States Food and Drug Administration and Department of Defense Shelf‐Life Extension Program of Pharmaceutical Products: Progress and Promise. J Pharmac Sci, 2014, 103, 1331-1336.
Shunkina, S., and B. Hromovyk. Methadone as an alternative analgesic for palliative patients. Pharmacia, 2016, 63, 21-28.
Friciu, M. Mihaela, et al. Stability of methadone hydrochloride for injection in saline solution. Can J Hosp Pharma, 2020, 73, 141.
Methadone Hydrochloride Injection, USP 200 mg/20 mL (10 mg/mL). US Food and Drug Administration.
De Winter, Sabrina, et al. Impact of temperature exposure on stability of drugs in a real-world out-of-hospital setting. Annals emerg med, 2013, 62, 380-387.
Swaroop, A. Prem, and D. Varun. A glimpse on expiry date of pharmaceutical dosage forms. Pharmanest Int J Adv Pharmaceut Sci, 2011, 2, 423-33.