Phentermine is a prescription medicine that reduces appetite. It may be an option for some people seeking help with weight loss, but a prescription depends on more than wanting to lose weight. Your health history, current medicines, and the risks of treatment all belong in the conversation.
If you are considering phentermine treatment in Houston, start by asking what makes it appropriate for your situation. At Image Weight Loss Centers, our approach includes a medical evaluation, a weight management plan, and ongoing monitoring. Here are the key points to understand before that visit.
What does phentermine do?
Phentermine works as an appetite suppressant and is taken by mouth. It can be habit-forming and should be used exactly as prescribed. It is intended to support a weight management program that also includes changes in eating and activity.
Who may be eligible to discuss it?
The prescribing criteria include an initial BMI of at least 30, or at least 27 with risk factors such as diabetes, high cholesterol, or controlled high blood pressure. BMI means body mass index.
These thresholds are a starting point for evaluation. The Endocrine Society recommends considering weight management medication for people who meet the drug’s criteria and have had difficulty losing weight or maintaining progress through lifestyle changes.
Your consultation should connect that general guidance to your own circumstances. Describe previous treatment, what helped, any side effects you experienced, and what made an earlier plan difficult to continue. A useful question is, “Why would you recommend phentermine for me rather than another approach?”
Is phentermine approved for long-term use?
Phentermine alone is FDA-approved for short-term use, meaning a few weeks. Some clinicians prescribe it longer off-label, but that is different from an FDA-approved long-term indication.
Phentermine combined with topiramate, sold as Qsymia, is a separate medication approved for chronic weight management.
Ask how long treatment is planned, why that duration is being considered, and when the decision will be reviewed. Do not assume that a refill means the plan should continue indefinitely.
Who should avoid phentermine?
The prescribing information lists several situations in which phentermine should not be used. These include:
• A history of cardiovascular disease, including stroke, certain heart conditions, or uncontrolled high blood pressure.
• An overactive thyroid, glaucoma, or an agitated state.
• Pregnancy or breastfeeding.
• A history of drug abuse or a relevant allergy to sympathomimetic medicines.
• Use of a monoamine oxidase inhibitor (MAOI) now or within the previous 14 days.
This is not a substitute for an individual safety review. Tell the prescriber about kidney disease, previous reactions to medicines, and any conditions you are being treated for. Ask the clinician to explain unfamiliar terms and how your history affects the recommendation.
Blood pressure deserves particular attention. The Endocrine Society advises against phentermine in people with uncontrolled blood pressure or a history of heart disease. A history of treated high blood pressure still needs a clinician’s assessment.
What should you bring to the medication review?
Prepare a list of prescriptions, over-the-counter medicines, vitamins, supplements, and allergies.
Include products you take only occasionally. MedlinePlus recommends bringing a medication list and writing down the questions you want answered.
Tell the clinician about any other weight loss products you use. Ask whether to avoid particular supplements or nonprescription products, and make sure your pharmacist has the same medication information. Also discuss alcohol use and whether treatment could affect driving or operating equipment.
If you work changing shifts or already have difficulty sleeping, mention that during the visit. Ask how the prescribed instructions would fit your routine, rather than borrowing someone else’s schedule or dose.
Which side effects need attention?
Phentermine can cause dry mouth, constipation, sleep problems, restlessness, and a fast or pounding heartbeat. It may also increase blood pressure. Ask which symptoms require a prompt call and what to do before taking another dose.
Stop taking phentermine and seek urgent medical evaluation for new unexplained shortness of breath, chest pain, fainting, or leg swelling, as its labeling directs.
What should follow-up cover?
Follow-up should assess whether treatment is helping and whether it remains safe. The Endocrine Society recommends frequent early review of weight management medication, including assessment of effectiveness and tolerability. Ask your clinician what that schedule means for your prescription.
Discuss what to track between appointments, such as changes in appetite, sleep, symptoms, or measurements the clinician requests. You should also know when a refill requires another evaluation and whom to contact if you cannot attend a planned visit.
If appetite suppression fades, contact your prescriber. The label advises discontinuing phentermine when tolerance develops, rather than increasing the dose.
Take only the amount prescribed, do not extend treatment on your own, and never share your medication.
What happens when the prescription ends?
Discuss maintenance before the end of treatment. Weight regain can occur after stopping weight management medication. Ongoing eating and activity habits remain part of maintaining progress.
Ask what support will continue, whether another treatment should be considered, and when to return. It helps to identify practical issues early: changes in your work schedule, the cost of follow-up, or a routine you find difficult to maintain.
Five questions to take to your appointment
• How do my medical history and current medicines affect whether phentermine is suitable?
• What benefits should we look for, and when will we reassess?
• How long is treatment planned, and is any proposed use off-label?
• What are the costs of medication, monitoring, and follow-up?
• What is the plan if I have side effects, do not respond, or stop treatment?
Discuss your options with Image Weight Loss Centers
Our Houston-area locations include Clear Lake, Pearland, Sugar Land, and Cypress/Jersey Village. Request a weight loss consultation to discuss available services and the evaluation process. The prescribing clinician can help you understand whether phentermine or another approach is appropriate for your needs.
General educational information for adults. Medication decisions require evaluation by a qualified prescribing clinician.
References
[1] MedlinePlus. Phentermine. medlineplus.gov/druginfo/meds/a682187.html
[2] Image Weight Loss Centers. Phentermine Weight Loss in Houston.
www.loseweightez.com/services/phentermine-weight-loss-clinic-in-houston/
[3] DailyMed. Phentermine hydrochloride prescribing information, updated May 2026.
dailymed.nlm.nih.gov/dailymed/drugInfo.cfm?setid=3d1d4dde-1c7f-4a20-b8f8-897b1b284f80
[4] Endocrine Society. Pharmacological Management of Obesity guideline.
www.endocrine.org/clinical-practice-guidelines/pharmacological-management-of-obesity
[5] NIDDK. Prescription Medications to Treat Overweight & Obesity.
www.niddk.nih.gov/health-information/weight-management/prescription-medications-treat-overweight-obesity
[6] MedlinePlus. Talking With Your Doctor. medlineplus.gov/talkingwithyourdoctor.html
