Adipex Retard

Adipex Retard



Gerot Lannach


Full Prescribing Info
1 capsule contains phentermine 15 mg as the polystyrene sulphonate, 0.17 mg propyl-4-hydroxybenzoate sodium and 0.34 mg ethyl-4-hydroxybenzoate sodium as stabilisers.
Excipients/Inactive Ingredients: Yellow beeswax, hydrated soybean oil, rape-seed oil, soybean lecithin, gelatin, glycerol 85%, Karion 83, ester of castor oil fatty acid with ethoxylated glycerin (Cremophor EL), titanium dioxide E171, sunset yellow E110, quinoline yellow E104, ethyl vanillin and p-methoxy-acetophenon.
Pharmacology: Adipex Retard contains phentermine, a centrally-stimulating substance that has also an anorectic effect. This effect is transient and decreases with the continued use of phentermine after a few weeks. Phentermine is bound to a non-absorbable ion-exchanger on a resinate basis and is slowly released in the intestines. The anorectic effect sets in after 1-3 hrs and lasts for at least 8 hours. Phentermine is barely metabolised and does not form any active metabolites. About 60% of the ingested phentermine dose are excreted unchanged on the 1st day. Five percent (5%) of the administered dose are metabolised by N-oxidation, with primarily N-hydroxyphentermine and to a lesser degree, the nitro metabolite being formed which, after passing the enterohepatic blood flow, are mainly excreted by the kidneys. Plasma half-life is 20 to 25 hrs. Adipex Retard has been shown to inhibit excessive appetite. It represses the sensation of hunger, thus, making it easier to follow dietary restrictions and achieve a decrease in weight.
Adjunctive therapy to diet, in patients with obesity and a body mass index (BMI) of 30 or higher, who have not responded to an appropriate weight reducing regimen alone.
Note: Short-term efficacy only has been demonstrated with regard to weight reduction. No significant data on changes in morbidity or mortality are yet available.
*How to calculate the body mass index (BMI): The BMI is the quotient of body weight (in kilograms) and the square of body height (in meters): (See equation.)

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Dosage/Direction for Use
General Advice: It is recommended that treatment should be conducted under the care of physicians experienced in the treatment of obesity. Secondary organic causes of obesity must be excluded by diagnosis before prescribing this drug. The management of obesity should be undertaken using a global approach which should include dietary, medical and psychotherapeutic methods.
Evening dosing should be avoided, as this agent may induce nervousness and insomnia.
Dosage: As a rule, 1 capsule daily. In exceptional cases the dose may be increased to 2 capsules daily.
Duration of Treatment: The duration of treatment is 4–6 weeks and should not exceed three months. If further treatment is planned after that, the next treatment cycle should be preceded by a therapy-free interval lasting at least as long as the previous therapy.
Method of Administration: The capsules should be taken with breakfast unchewed and with plenty of liquid.
Symptoms of acute overdosage include nervous restlessness, motoric stereotypes, tremor, hyperreflexia, fever, tachypnea, vertigo, hallucinations, changes in blood pressure, arrhythmias, nausea, emesis, diarrhoea and even respiratory and circulatory collapse, convulsions, somnolence and coma.
Therapy: Apart from forced acidic diuresis, the treatment of overdosage is mainly symptomatic; sedation may be necessary. Chlorpromazine may antagonise the CNS stimulation.
Because of the risk of inducing convulsions, caution is required if gastric lavage is performed.
Hypersensitivity to the active ingredient or other sympathomimetic amines; pulmonary artery hypertension; severe arterial hypertension; current or past medical history of cardiovascular or cerebro-vascular diseases; hyperthyreosis, pheochromocytoma, glaucoma, prostatic adenoma, renal insufficiency; current or past medical history of psychiatric disorders, including anorexia nervosa and depression; propensity towards drug abuse, known alcoholism; children below 12 years and elderly patients.
Combination drug therapy with any other centrally acting anorectic agent is contraindicated due to the increased risk of potentially fatal pulmonary artery hypertension.
Do not use in combination with MAO-inhibitors or within 2 weeks after their withdrawal.
Cases of severe, often fatal, pulmonary artery hypertension have been reported in patients who have received anorectics of the type in Adipex Retard. An epidemiological study has shown that anorectic intake is a risk factor involved in the development of pulmonary artery hypertension and that the use of anorectics is strongly associated with an increased risk for this adverse drug reaction. In view of this rare but serious risk, it must be emphasised that: Careful compliance with the indication and the duration of treatment is required; duration of treatment greater than 3 months and a BMI ≥30 [kg/m2] increase the risk of pulmonary artery hypertension; the onset or aggravation of exertional dyspnea suggests the possibility of occurrence of pulmonary artery hypertension. Under these circumstances, treatment should be immediately discontinued and the patient referred to a specialist unit for investigation.
Special Precautions
Prolonged treatment may give rise to pharmacological tolerance and drug-dependence and more rarely, to severe psychotic disorders in predisposed patients.
Rarely, cases of cardiac and cerebrovascular accidents have been reported, often following rapid weight loss. Special care should be taken to ensure gradual and controlled weight loss in obese patients who are subject to a risk of vascular disease. Adipex Retard should not be prescribed in patients with current or a past medical history of cardiovascular or cerebrovascular disease.
This anoretic drug should be used with caution in epileptic patients.
Even when used as prescribed, this drug may affect reactivity to a degree where the ability to drive a motor vehicle or operate machinery is impaired. This is the case particularly with concomitant intake of alcohol.
Information for Patients: Losing weight is only possible if food intake is reduced. A weight loss already achieved can only be maintained if dietary rules are systematically followed. Anorectics alone have no weight-reducing effect.
Chances of losing weight are greater if food with low nutritive value (lean meat, fruits, vegetables) is preferred, whereas fats and carbohydrates (products containing sugar or flour, potatoes) should be largely restricted. After discontinuation of Adipex Retard treatment, the low-calorie diet should be continued for at least 6 weeks.
The physician should be informed if the patient is using any other drugs [prescription or over-the-counter (OTC)] before starting treatment with Adipex Retard. Many nonprescription drugs eg, cough and asthma remedies, medicaments against cold or flu, contain active ingredients that may increase the adverse effects likely to occur with Adipex Retard. It is especially important to inform the physician of the use of Adipex Retard if the patient has to undergo surgery, since the concomitant administration of inhalation anesthetics may induce cardiac arrhythmias.
Use In Pregnancy & Lactation
Phentermine is contraindicated during the first three months of pregnancy and during lactation. In the further course of pregnancy a careful benefit-risk assessment has to be made.
Side Effects
Undesirable effects on the central nervous system: The prolonged use of this agent is associated with a risk of pharmacological tolerance, dependence and withdrawal syndrome.
The most common adverse reactions which have been described are: psychotic reactions or psychosis, depression, nervousness, agitation, sleep disorders and vertigo. Convulsions have been reported.
Undesirable effects on the cardiovascular system: The most common reported reactions are tachycardia, palpitations, hypertension, precordial pain.
Rarely, cases of cardiavascular or cerebro-vascular accidents have been described in patients treated with anorectic agents. In particular stroke, angina, myocardial infarction, cardiac failure and cardiac arrest have been reported.An epidemiological study has shown that the intake of anorectics is a risk factor involved in the development of pulmonary artery hypertension and that the use of anorectics is strongly associated with an increased risk for this adverse drug reaction. Cases of pulmonary artery hypertension have been reported in patients treated with this agent. Pulmonary artery hypertension is a rare, but severe and often fatal disease. The occurrence or aggravation of exertional dyspnea is usually the first clinical sign and requires treatment discontinuation and investigation in a specialised unit. (see Warnings)
Even when used as prescribed, Adipex Retard may affect reactivity to a degree where the ability to drive a motor vehicle or operate machinery is impaired. This is the case particularly with concomitant intake of alcohol.
In addition, the following side effects have occurred in rare cases: headache, irritability, unpleasant taste, dry mouth, nausea, emesis, diarrhea, constipation, arrhythmias, sexual dysfunction, micturition difficulties, urticaria, exanthema.
Drug Interactions
Phenothiazine and other psychotropic drugs such as chlorpromazine or haloperidol, as well as tri- or tetracyclic antidepressants, may reduce the effect of phentermine. The hypotensive effect of guanethidine and other antihypertensives may be antagonised by phentermine. Combined administration with monoamine oxidase inhibitors (MAOIs) may cause hypertensive crisis. The effect of phentermine may be potentiated by other CNS-stimulants as well as caffeine.
Concomitant use of inhalation anesthetics may lead to cardiac arrhythmias.
Store at room temperature not exceeding 25°C. Protect from light.
Shelf-Life: 60 months.
MIMS Class
Anti-Obesity Agents
ATC Classification
A08AA01 - phentermine ; Belongs to the class of centrally acting antiobesity products. Used in the treatment of obesity.
Retard cap 15 mg x 100's.
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