Injection
Tirzepatide + B12
A weekly dual-action GLP-1/GIP injection for meaningful weight loss and appetite control, paired with vitamin B12 for energy.
Starting at $198/mo
Weight lossControlledShort-term
Phentermine
RxPrescription onlyTaken by mouth · Once a day · 37.5 mg · Weight loss · Controlled · Short-term
Starting at $109/mo
Phentermine, a controlled-schedule stimulant approved for short-term weight loss (12 weeks or less). Requires video medical consultation. Works by suppressing appetite and increasing energy. Use only under close physician supervision.
How many tablets per month?
MonthlyEvery 3 months
30 tabletsper month
You'll receive 30 tablets per month. $129 billed monthly. Cancel anytime.
Real prices from our pharmacy. Longer plans cost less per month and are billed up front. Pause or cancel anytime.
- FDA-approved for short-term weight loss
- Strong appetite suppression
- Video consultation with physician required
Every plan includes
- Personalized, physician-guided plan
- 30 tablets per month, monthly and 3-month
- Dispensed by a US-licensed compounding pharmacy
- Unlimited protocol adjustments and messaging
- Ongoing support and check-ins
- Pause or cancel anytime
- Reviewed by our in-house physicians
- Physician-guided care
- Ongoing, expert support
- 100% online
- Free, discreet shipping
What is Phentermine?
(sympathomimetic amine, Schedule IV)
Phentermine is an FDA-approved appetite suppressant similar to amphetamine. It stimulates the central nervous system to reduce appetite and increase energy. Approved use is 12 weeks or less. Requires medical screening and ongoing supervision due to cardiovascular and neurological effects.
- How it is taken
- Taken by mouth
- How often
- Once a day
- Dose range
- 37.5 mg
- Form
- Weight loss · Controlled · Short-term
Short-term
FDA-approved, 12 weeks maximum
Phentermine is a controlled medication; long-term use risks dependence and cardiovascular issues. Approved only for 12 weeks of continuous use. Your physician will evaluate you with video consultation before prescribing.
How it works,
week by week.
Day 1
Video consultation with a US-licensed physician. Medical screening: blood pressure, heart rate, ECG may be required. Detailed discussion of risks, benefits, and contraindications. Informed consent required.
Week 1
Start your dose (low dose for phentermine). Appetite suppression often noticeable within days. Energy increases. Monitor for jitteriness, heart palpitations, or insomnia.
Weeks 2–4
Weight loss accelerates. Appetite remains suppressed. Your physician checks in weekly or biweekly to monitor cardiovascular and psychological effects.
Weeks 5–12
Steady, significant weight loss. Physician continues close monitoring. At week 12 (or sooner if phentermine alone), plan for pause or switch to longer-term option.
Week 12+
Maintenance or transition: if using phentermine alone, pause it (cannot use continuously). Phentermine/topiramate ER may continue if tolerated. Your physician guides next steps.
What you may notice,
and when.
Rapid weight loss
3–5 kg in 12 weeks (phentermine); up to 10% body weight (combination)
Energy boost
increased alertness and motivation (stimulant effect)
Cardiovascular monitoring
blood pressure and heart rate require close tracking
Psychiatric vigilance
mood, anxiety, and sleep need supervision
Individual results vary. Benefits reflect what Zepym Health members commonly report to their physician at check-ins; they are not the results of a clinical trial.
Safety first:
what to know before you start.
Important safety information and common side effects
Phentermine and phentermine/topiramate are controlled medications with significant risks. Do not use with uncontrolled high blood pressure, heart disease, recent heart attack or stroke, glaucoma, or history of substance abuse. Cardiovascular effects include increased heart rate, elevated blood pressure, and palpitations. Neurological effects include anxiety, insomnia, tremor, and (with topiramate combination) cognitive impairment. Phentermine/topiramate is absolutely teratogenic (causes birth defects); women of childbearing potential must use strict contraception. Tell your physician about all medications, cardiovascular disease, psychiatric conditions, and any history of drug or alcohol abuse. Stop and seek care for chest pain, severe headache, palpitations, shortness of breath, or psychiatric symptoms.
The research behind
phentermine.
Phentermine is an appetite suppressant approved for short-term use. The evidence is short trials; no long-term outcome trial of phentermine alone was found.
- Labela few weeks
The FDA label approves phentermine as a short-term adjunct, a few weeks, alongside diet, exercise and behavior change.
Adipex-P prescribing information (FDA label, copy on Drugs.com) - Trial length2 to 24 weeks
The obesity guideline table lists phentermine 37.5 mg a day in trials of 2 to 24 weeks. Those trials are short; the table's effect sizes are not readable enough to quote.
Endocrine Society obesity guideline, drug table - Two yearsno trial found
No randomized trial of phentermine alone lasting two years was found. The longer figures people quote belong to the phentermine-topiramate combination, not to phentermine alone.
PubMed search, no trial found
What the studies found
- Approved for short-term use alongside diet and exercise in adults with obesity (Adipex-P prescribing information, FDA label).
- Weight loss in trials of 2 to 24 weeks at 37.5 mg a day; the trials are short and their effect sizes are not verified here (Endocrine Society obesity guideline table).
- Acts as a sympathomimetic appetite suppressant; the human appetite effect is the basis of the label (Adipex-P prescribing information).
This is the 37.5 mg tablet in the pharmacy catalog. Generic tablets are not the brand product, and compounded forms were not studied.
What this does not say
- Phentermine is a stimulant. Its label asks prescribers to weigh its risks, including raised blood pressure and heart rate.
- The label limits use to a few weeks; a plan longer than that has no trial behind it in these sources.
- Taking it late in the evening can cause insomnia.
The research
behind it.
Phentermine produces mean weight loss of 3–5 kg over 12 weeks in clinical trials, greater than placebo. Effects decline after 12 weeks; tolerance develops.
Phentermine is only for people without uncontrolled high blood pressure, heart disease, or certain psychiatric conditions. Your physician must screen you and monitor cardiovascular and psychological effects.
GLP-1 beyond the scale:
what the research showsHeart, kidneys, liver, sleep and joints: the trials, with their numbers and their limits.Read the researchMicrodosing GLP-1:
what we know, and what we don’tLower doses are everywhere online. Here is what has actually been studied, and how our physicians use dose.Read the research
what the research showsHeart, kidneys, liver, sleep and joints: the trials, with their numbers and their limits.Read the researchMicrodosing GLP-1:
what we know, and what we don’tLower doses are everywhere online. Here is what has actually been studied, and how our physicians use dose.Read the research
Getting started
takes a few minutes.
- 1
Connect with a physician
Answer a few questions online and a US-licensed physician reviews your health, history and goals to make sure treatment is right for you. 100% online. No in-person visit required.
- 2
Get your discreet shipment
If approved, your treatment is compounded by a US-licensed, LegitScript-certified pharmacy, inspected for quality, and shipped discreetly to your door.
- 3
Receive continuous support
Start with one goal, then keep building over time. Unlimited physician messaging, easy refills and dose adjustments, all from the Zepym Health app.
Frequently asked questions
Contact supportHow do I take Phentermine?
Taken by mouth, once a day, in the morning. The starting prescription is 1 tablet (37.5 mg) each time. Your physician sets your own dose and it is printed on your label.
How much arrives in each shipment?
30 tablets at the starting strength, shipped to your door from a licensed US pharmacy.
Is it a controlled substance?
Yes. The law requires a live video visit with the physician before it can be prescribed.
Why is phentermine limited to 12 weeks?
Phentermine's effects diminish over time (tolerance), and long-term use increases risks of dependence, hypertension, and cardiovascular issues. 12 weeks is the FDA-approved limit for continuous use. Your physician may pause and restart if appropriate.
Why are these medications controlled?
Phentermine is similar to amphetamine; it stimulates the central nervous system and carries risks of dependence, cardiovascular effects, and psychiatric symptoms. Schedule IV reflects these risks. Strict medical supervision is required.
Can I use phentermine longer than 12 weeks?
Continuous phentermine use is FDA-approved only for 12 weeks or less. After that, tolerance develops and risks increase. Your physician may pause (typically 2–4 weeks) and restart, or switch to the combination (phentermine/topiramate ER, which is approved for longer use).
What if I'm a woman of childbearing age?
Phentermine/topiramate ER is teratogenic (causes birth defects) and absolutely contraindicated in pregnancy. Women of childbearing potential must use highly effective contraception. Phentermine alone is safer in pregnancy, but not recommended. Discuss with your physician.
What happens after 12 weeks?
If using phentermine alone: pause it, then your physician may restart after 2–4 weeks. If using phentermine/topiramate ER: you may continue if tolerated, or transition to a non-controlled option (GLP-1, metformin, etc.) for maintenance.
Phentermine educational content reviewed by our physician
Scott Nass, MD Doctor of Medicine, board-certified in Family Medicine
Charles R. Drew University and David Geffen School of Medicine at UCLA. Family Medicine residency at Ventura County Medical Center.
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References
- 1.Phentermine efficacy and cardiovascular safety: randomized controlled trials. Obesity, 2019
- 2.Phentermine/topiramate ER for long-term weight loss (Qsymia): efficacy and safety. Lancet, 2012 (Gadde KM et al.)
Prescription products require an online evaluation with a licensed medical professional who will determine if a prescription is appropriate. Products are compounded by a licensed pharmacy. The FDA has not reviewed or approved compounded products for any use for safety, efficacy, or quality. Compounded medications are not FDA-approved brand-name products.