Phentermine side effects

Phentermine is a stimulant that can cause a range of side effects, from common issues like dry mouth and insomnia to rare but serious heart and lung problems . The side effects are typically most noticeable when you first start taking the medication .

Here is a breakdown of the potential side effects, organized by category and severity:

These side effects are relatively common and often improve as your body adjusts to the medication .

• Body System Common Side Effects Management Tips
• Central Nervous System Insomnia, restlessness, nervousness, dizziness, headache, tremors Take your dose early in the morning to prevent sleep problems. Avoid caffeine .
• Cardiovascular Fast/irregular heartbeat (palpitations), increased blood pressure Monitor your heart rate and blood pressure if advised by your doctor. Avoid stimulants like caffeine .
• Gastrointestinal Dry mouth, unpleasant taste, constipation, diarrhea For dry mouth, sip water often or chew sugar-free gum. For constipation, eat high-fiber foods and stay hydrated .
• Other Changes in sexual desire or ability (impotence) Discuss any changes with your healthcare provider.

While less common, phentermine can cause serious side effects that require immediate medical attention . Call your doctor right away or seek emergency care if you experience:

• Body System Serious Side Effects & Symptoms Notes
• Cardiovascular (Heart & Lungs) Chest pain, shortness of breath (even with mild exertion), swelling in ankles/feet, fainting, decreased ability to exercise These can be signs of serious heart valve problems or a rare lung condition called pulmonary arterial hypertension .
• Central Nervous System (Mental Health) Severe mood changes, agitation, aggression, hallucinations (seeing/hearing things), feeling unusually suspicious or confused Phentermine may cause psychosis or other severe psychiatric issues, especially with misuse .
• Allergic Reaction Rash, hives, itching, swelling of the face/lips/tongue/throat, trouble breathing This is a medical emergency. Stop taking the medication and get help immediately.

You should contact your doctor if you:

• Experience any of the serious side effects listed above .
• Have side effects that are bothersome or do not go away .
• Feel the medication is not working as well after a few weeks (do not increase the dose on your own) .
• Have not lost at least 4 pounds in 4 weeks .