Side effects may include headache, insomnia, difficulty thinking, depression, anxiety, rapid heart rate, dry mouth, nose and throat irritation, constipation, and numbness or tingling sensations. Some people have had suicidal thoughts. Others have developed kidney stones.
Rarely, people taking phentermine have developed heart valve problems. They may also be at risk for pulmonary hypertension. Phentermine may be habit forming, and can make it dangerous to drive or operate machinery.
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Important: This content reflects information from various individuals and organizations and may offer alternative or opposing points of view. It should not be used for medical advice, diagnosis or treatment. As always, you should consult with your healthcare provider about your specific health needs.