From the Research
Phentermine can potentially cause back pain as a side effect, although it is not among the most commonly reported adverse effects. Phentermine is a stimulant medication prescribed for short-term weight management, typically at doses of 15-37.5 mg taken once daily in the morning. Back pain may occur due to phentermine's effects on the central nervous system and muscles, as it can increase muscle tension or alter how pain signals are processed. If you experience back pain while taking phentermine, you should report this to your healthcare provider, who might recommend adjusting the dosage, trying alternative weight management medications, or implementing pain management strategies, such as those recommended in the study 1. According to the study 2, a case of rhabdomyolysis associated with the use of phentermine was reported, which resulted in significant back, shoulder, and radiating inguinal pain. However, it is essential to note that this was a case where the patient took double the recommended dosage of phentermine. For managing acute low back pain, the study 1 recommends first-line pharmacologic agents such as acetaminophen and NSAIDs, and muscle relaxants can be used for spasms and pain reduction. Additionally, the study 3 suggests that NSAIDs may be superior to placebo for reducing pain in acute and chronic low back pain, but their use should be cautious in people who may be at greater risk of experiencing adverse events. Do not stop taking phentermine abruptly without medical guidance, as this could lead to withdrawal symptoms. Other more common side effects of phentermine include increased heart rate, elevated blood pressure, insomnia, dry mouth, constipation, and nervousness, which your doctor should monitor during treatment. It is crucial to weigh the benefits and risks of phentermine and other medications for low back pain, considering the latest evidence and guidelines, such as those provided in the studies 4, 5, and 3.