Short answer: The Lomaira label lists phentermine side effects without percentages: palpitations, fast heartbeat, raised blood pressure, restlessness, dizziness, insomnia, tremor, headache, dry mouth, unpleasant taste, diarrhea, constipation, hives, impotence and libido changes. Its warnings cover rare primary pulmonary hypertension and heart valve disease, tolerance, abuse and alcohol. Lomaira has no boxed warning.
What Lomaira is approved for: Lomaira is approved as a short-term (a few weeks) add-on to a weight-loss plan of exercise, behavior change and fewer calories, for obesity in people with a starting BMI of 30 kg/m2 or more, or 27 kg/m2 or more with other risk factors such as controlled high blood pressure, diabetes or high cholesterol (Indications and Usage). Phentermine is a Schedule IV controlled substance (Drug Abuse and Dependence).
Source
LOMAIRA (phentermine hydrochloride USP) tablets, 8 mg, CIV, prescribing information. KVK-Tech. DailyMed, version published December 20, 2023. DailyMed setid cde9fb09-e5af-434d-8874-e4f9f974d893
No. The current Lomaira label has no boxed warning.
These are the label's own numbers from the Adverse Reactions section. Where the label compares with placebo (a dummy treatment), both columns are shown, so you can see how much more often a reaction happened on Lomaira.
| Body system | Reactions the label lists |
|---|---|
| Cardiovascular | Primary pulmonary hypertension and/or regurgitant cardiac valvular disease, palpitation, tachycardia, elevation of blood pressure, ischemic events |
| Central Nervous System | Overstimulation, restlessness, dizziness, insomnia, euphoria, dysphoria, tremor, headache, psychosis |
| Gastrointestinal | Dryness of the mouth, unpleasant taste, diarrhea, constipation, other gastrointestinal disturbances |
| Allergic | Urticaria |
| Endocrine | Impotence, changes in libido |
The label lists these as adverse reactions identified with phentermine. It gives no percentages and no placebo comparison.
In short trials, people taking appetite-suppressant ("anorectic") drugs with a diet lost more weight on average than people on placebo and diet, but the extra loss was only a fraction of a pound a week. The label says the overall effect over diet alone must be considered clinically limited.
Stopping suddenly after long use of high doses leads to extreme tiredness and depression, with changes on sleep EEG. Long-term misuse can cause severe skin problems, marked insomnia, irritability, hyperactivity, personality changes and, at worst, psychosis.
Signs of overdose include restlessness, tremor, overactive reflexes, fast breathing, confusion, aggression, hallucinations and panic, then tiredness and depression. Heart effects include irregular heartbeat and high or low blood pressure; stomach effects include nausea, vomiting, diarrhea and cramps.
Tolerance (a weaker effect over time) has been seen with all drugs of this class where it was looked for.
The Warnings and Precautions part of the label lists these. Each line gives the label's heading and what it means in plain words.
Who should not use it. People with a history of heart or blood vessel disease (such as coronary artery disease, stroke, irregular heartbeat, heart failure or uncontrolled high blood pressure), within 14 days of an MAOI, with an overactive thyroid, glaucoma, agitated states or a history of drug abuse, during pregnancy or nursing, or with a known allergy or unusual reaction to sympathomimetic amines.
Other weight-loss drugs. Lomaira is approved only as short-term use on its own. Safety and effectiveness with other weight-loss drugs (prescription, over-the-counter or herbal) or with SSRIs such as fluoxetine or sertraline have not been established, so taking them together is not recommended.
Primary pulmonary hypertension. This rare, often fatal lung disease has been reported with phentermine plus fenfluramine or dexfenfluramine, and rarely with phentermine alone. The first symptom is usually shortness of breath; others are chest pain, fainting or leg swelling. Treatment is stopped if these appear without explanation.
Heart valve disease. Serious leaky heart valves have been reported in people who took phentermine with fenfluramine or dexfenfluramine, and rarely with phentermine alone. The role of phentermine has not been established.
Tolerance. When the appetite effect wears off, the label says the dose should not be raised above the recommended dose; instead the drug should be stopped.
Driving and machinery. Phentermine may impair the ability to drive or operate machinery.
Abuse and dependence. Phentermine is chemically related to amphetamine, and related stimulants have been widely abused. The label says the smallest workable amount should be prescribed or dispensed at one time to limit overdose.
Alcohol. Drinking alcohol with phentermine may cause an adverse reaction.
High blood pressure. Caution is used in people with even mild high blood pressure, because phentermine can raise blood pressure.
Diabetes medicines. People with diabetes on insulin or oral diabetes medicines may need a lower dose of those medicines.
Kidney impairment. Phentermine was not studied in kidney impairment. Most of it leaves through the urine, so higher levels are expected and caution is used.
From the Warnings and Information for Patients sections (the label has no separate Medication Guide) that comes with Lomaira:
Dose Track has a side-effect log. Each entry records the symptom, a severity (none, mild, moderate, severe or life-threatening), the date and an optional note, and can be tied to a specific dose or logged on its own. The history screen shows what you logged over time, which makes it easier to tell your prescriber when a reaction started and whether it is easing. The app records what you enter; it does not judge whether a symptom is serious. For anything on the label's call-your-doctor list, call your doctor.
This page is what the FDA label says, in plain words. It is not medical advice. Follow your prescriber, and ask them or your pharmacist about anything here.