SELEGILINE Drug Interactions: What You Need to Know

INTERACTIONS

7.1 Serotonergic Drugs Serious, sometimes fatal, central nervous system (CNS) toxicity referred to as the “serotonin syndrome” has been reported with the combination of nonselective MAOIs and serotonergic drugs. Use of EMSAM with these drugs is contraindicated <span class="opacity-50 text-xs">[see Contraindications (4) and Warnings and Precautions (5.2) ]</span> .

7.2 Tyramine EMSAM has the capacity to inhibit intestinal MAO, which is responsible for the catabolism of tyramine in food and beverages. As a result of this inhibition, large amounts of tyramine may enter the systemic circulation and precipitate a sudden, large rise in blood pressure or hypertensive crisis <span class="opacity-50 text-xs">[see Warnings and Precautions (5.3) and Clinical Pharmacology (12.2) ]</span> . A diet low in tyramine content may be necessary to avoid this interaction. Studies to evaluate the potential for EMSAM to inhibit tyramine metabolism have been conducted and, overall, the data for EMSAM 6 mg per 24 hours support a recommendation that a modified diet is not required at this dose. Due to the more limited data available for EMSAM 9 mg per 24 hours and the results from the Phase I tyramine challenge study in fed volunteers administered EMSAM 12 mg per 24 hours, patients receiving these doses should follow Dietary Modifications Required for Patients Taking EMSAM 9 mg per 24 hours and 12 mg per 24 hours below <span class="opacity-50 text-xs">[see Clinical Pharmacology (12.2) ]</span> .

Dietary Modifications

Required for Patients Taking EMSAM 9 mg per 24 hours and 12 mg per 24 hours The foods and beverages listed in Table 5 should be avoided beginning on the first day of EMSAM 9 mg per 24 hours or 12 mg per 24 hours treatment, and should continue to be avoided for 2 weeks after a dose reduction to EMSAM 6 mg per 24 hours or following the discontinuation of EMSAM 9 mg per 24 hours or 12 mg per 24 hours.

Table

5. Food and Beverages to Avoid and Those which are Acceptable [see References (15) ] Class of Food and Beverage Tyramine-Rich Foods and Beverages to Avoid Acceptable Foods and Drinks, Containing No or Little Tyramine Meat, Poultry, and Fish Air dried, aged and fermented meats, sausages and salamis (including cacciatore, hard salami and mortadella); pickled herring; and any spoiled or improperly stored meat, poultry, and fish (e.g., foods that have undergone changes in coloration, odor, or become moldy); spoiled or improperly stored animal livers Fresh meat, poultry, and fish, including fresh processed meats (e.g., lunch meats, hot dogs, breakfast sausage, and cooked sliced ham)

Vegetables

Broad bean pods (fava bean pods) All other vegetables Dairy Aged cheeses Processed cheeses, mozzarella, ricotta cheese, cottage cheese, and yogurt Beverages All varieties of tap beer and beers that have not been pasteurized so as to allow for ongoing fermentation Concomitant use of alcohol with EMSAM is not recommended. (Bottled and canned beers and wines contain little or no tyramine.)

Miscellaneous

Concentrated yeast extract (e.g., Marmite), sauerkraut, most soybean products (including soy sauce and tofu), OTC supplements containing tyramine Brewer’s yeast, baker’s yeast, soy milk, commercial chain restaurant pizzas prepared with cheeses low in tyramine

7.3 Sympathomimetic Amines and Buspirone The use of EMSAM with sympathomimetic amines or buspirone may produce substantial elevations in blood pressure. Therefore, monitor blood pressure if EMSAM is used with any of the following drugs: buspirone, amphetamines, and cold products or weight-reducing preparations that contain sympathomimetic amines (e.g., pseudoephedrine, phenylephrine, phenylpropanolamine, and ephedrine).

7.4 Effect of Other Drugs on EMSAM Carbamazepine is contraindicated with MAOIs, including selegiline <span class="opacity-50 text-xs">[see Contraindications (4) , Warnings and Precautions (5.3) and Clinical Pharmacology (12.3) ]</span> . No dose adjustment for EMSAM is needed when EMSAM is used concomitantly with alcohol, alprazolam, ibuprofen, olanzapine, risperidone, levothyroxine, and CYP3A4 inhibitors (e.g., ketoconazole). No clinically meaningful change in selegiline exposure was seen when EMSAM was co-administered with alcohol, alprazolam, ibuprofen, olanzapine, risperidone, levothyroxine, and ketoconazole <span class="opacity-50 text-xs">[see Clinical Pharmacology (12.3) ]</span> .

7.5 Effect of EMSAM on Other Drugs Use of alcohol while taking EMSAM is not recommended, even though EMSAM has not been shown to increase the impairment of mental and motor skills caused by alcohol (0.75 mg per kg) <span class="opacity-50 text-xs">[see Clinical Pharmacology (12.3) ]</span> . Monitor blood pressure if sympathomimetic agents (e.g., phenylpropanolamine (PPA) or pseudoephedrine) are used with EMSAM, even though selegiline does not appear to affect the pharmacokinetics of PPA or pseudoephedrine <span class="opacity-50 text-xs">[see Clinical Pharmacology (12.3) ]</span> . No dose adjustment of alprazolam, ibuprofen, levothyroxine, olanzapine, risperidone, warfarin, or strong CYP3A4 inhibitors (e.g., ketoconazole) is necessary when these drugs are used in combination with EMSAM. EMSAM had no clinically relevant effect on pharmacokinetics of these drugs.

4 CONTRAINDICATIONS

• EMSAM (selegiline transdermal system) is contraindicated with selective serotonin reuptake inhibitors (SSRIs, e.g., fluoxetine, sertraline, and paroxetine); serotonin and norepinephrine reuptake inhibitors (SNRIs, e.g., venlafaxine and duloxetine); the tricyclic antidepressants clomipramine and imipramine, the opiate analgesics meperidine, tramadol, methadone, pentazocine, and propoxyphene; and the antitussive agent dextromethorphan because of a risk of serotonin syndrome when EMSAM is used with these agents [see Warnings and Precautions (5.2) and Drug Interactions (7.1) ] .
• Carbamazepine is contraindicated with EMSAM because of a possible increased risk of hypertensive crisis [see Warnings and Precautions (5.3) and Clinical Pharmacology (12.3) ] .
• After stopping treatment with drugs contraindicated with EMSAM, a time period equal to 4 to 5 half-lives (approximately one week) of the drug or any active metabolite should elapse before starting therapy with EMSAM. Because of the long half-life of fluoxetine and its active metabolite, at least 5 weeks should elapse between discontinuation of fluoxetine and initiation of treatment with EMSAM.
• At least 2 weeks should elapse after stopping EMSAM before starting therapy with any drug that is contraindicated with EMSAM.
• EMSAM is contraindicated in patients less than 12 years of age because of the potential for a hypertensive crisis [see Use in Specific Populations (8.4) and Clinical Pharmacology (12.3) ] .
• EMSAM is contraindicated in patients with pheochromocytoma because MAOIs may precipitate a hypertensive crisis in such patients.
• Serotonergic drugs: selective serotonin reuptake inhibitors (SSRIs), serotonin and norepinephrine reuptake inhibitors (SNRIs), clomipramine and imipramine, meperidine, tramadol, methadone, pentazocine, and propoxyphene; and the antitussive agent dextromethorphan should not be used with EMSAM because of a risk of serotonin syndrome ( 4 , 5.2 ).
• Carbamazepine should not be used with EMSAM ( 4 , 5.3 ).
• After stopping treatment with contraindicated medication, a time period equal to 4 to 5 half-lives (approximately one week) of the drug or any active metabolite should elapse before starting therapy with EMSAM. Because of the long half-life of fluoxetine and its active metabolite, at least 5 weeks should elapse between discontinuation of fluoxetine and initiation of treatment with EMSAM ( 4 ).
• At least 2 weeks should elapse after stopping EMSAM before starting therapy with a drug that is contraindicated with EMSAM ( 4 ).
• EMSAM is contraindicated in patients less than 12 years of age ( 4 , 8.4 ).
• Pheochromocytoma ( 4 ).

AND PRECAUTIONS

• May cause hypertension above 2.5 mg/day (5.1)
• May cause serotonin syndrome when used with antidepressants (5.2)
• May cause falling asleep during activities of daily living (5.3)
• May cause hypotension/orthostatic hypotension (5.4)
• May cause or exacerbate dyskinesia (5.5)
• May cause hallucinations and psychotic-like behavior (5.6)
• May cause problems with impulse control and compulsive behaviors (5.7)
• Abrupt discontinuation may cause hyperpyrexia and confusion (5.8)
• May cause irritation of the buccal mucosa ( 5.9 )
• Increased risk for patients with phenylketonuria ( 5.10 )

5.1 Hypertension ZELAPAR should not be used at daily doses exceeding those recommended (2.5 mg/day) because of the risks associated with non-selective inhibition of MAO <span class="opacity-50 text-xs">[see Drug Interactions (7.3) and Clinical Pharmacology (12.2) ]</span>. The selectivity of ZELAPAR for MAO-B may not be absolute even at the recommended daily dose of 2.5 mg daily. The selectivity of MAO-B inhibitors typically decreases, and it is ultimately lost as the dose is increased beyond recommended doses. Hypertensive reactions associated with ingestion of tyramine-containing foods have been reported even in patients taking the recommended daily dose of swallowed selegiline, a dose which is generally believed to be selective for MAO-B. Selectivity for MAO-B inhibition is gradually lost with increasing daily doses. An increase in tyramine sensitivity for blood pressure responses appears to begin at a dose of 5 mg ZELAPAR daily <span class="opacity-50 text-xs">[see Drug Interactions (7.5) ]</span> . However, the precise dose at which ZELAPAR becomes a non-selective inhibitor of all MAO enzymes in individual patients is unknown. Reports of hypertensive reactions have occurred in patients who ingested tyramine-containing consumables (i.e., food or drink) while receiving swallowed selegiline at the recommended dose (a dose believed to be relatively selective for MAO-B). The safe use of ZELAPAR at doses above 2.5 mg daily without dietary tyramine restrictions has not been established. A pharmacodynamic study showed increased tyramine sensitivity for increasing blood pressure and decreased selectivity for MAO-B with dosing above the recommended level (2.5 mg daily) <span class="opacity-50 text-xs">[see Clinical Pharmacology (12.2) ]</span>. Uncontrolled hypertension has been reported when taking the recommended dose of swallowed selegiline and a sympathomimetic medication (ephedrine). After starting ZELAPAR, monitor patients for new onset hypertension or exacerbation of hypertension that is not adequately controlled.

5.2 Serotonin Syndrome Serotonin syndrome and hyperpyrexia have been reported with the combined treatment of an antidepressant (e.g., selective serotonin reuptake inhibitors-SSRIs, serotonin-norepinephrine reuptake inhibitors-SNRIs, tricyclic antidepressants, tetracyclic antidepressants, triazolopyridine antidepressants) and a non-selective MAOI (e.g., phenelzine, tranylcypromine) or selective MAO-B inhibitors, such as selegiline (ELDEPRYL), rasagiline (AZILECT), and olanzapine (Zydis) selegiline (ZELAPAR). Serotonin syndrome is a potentially serious condition, which can result in death. Typical clinical signs and symptoms include behavioral and cognitive/mental status changes (e.g., confusion, hypomania, hallucinations, agitation, delirium, headache, and coma), autonomic effects (e.g., syncope, shivering, sweating, high fever/hyperthermia, hypertension, hypotension, tachycardia, nausea, diarrhea), and somatic effects (e.g., muscular rigidity, myoclonus, muscle twitching, hyperreflexia manifested by clonus, and tremor). In the post-marketing period, fatal and non-fatal cases of serotonin syndrome have been reported in patients treated with antidepressants concomitantly with ZELAPAR <span class="opacity-50 text-xs">[see Contraindications (4) and Drug Interactions ( 7.1 , 7.2 , 7.3 ) ]</span>. Clinical studies of ZELAPAR did not allow concomitant use of any selective serotonin re-uptake inhibitor (e.g., fluoxetine-Prozac, fluvoxamine-Luvox, paroxetine-Paxil, sertraline, venlafaxine-Effexor, or nefazodone-Serzone) or any non-selective serotonin reuptake inhibiting antidepressant drug (except when taken at a low dose and only at night for the purpose of effective sleep) with ZELAPAR. Because the mechanisms responsible for these reactions are not fully understood, avoid the combination of ZELAPAR with any antidepressant. At least 14 days should elapse between discontinuation of ZELAPAR and initiation of treatment with a SSRI, SNRI, tricyclic, tetracyclic, or triazolopyridine antidepressant. In patients taking antidepressants with a long half-life (e.g., fluoxetine and its active metabolite), allow at least five weeks (perhaps longer, especially if fluoxetine has been prescribed chronically and/or at higher doses) to elapse between discontinuation of fluoxetine and initiation of ZELAPAR <span class="opacity-50 text-xs">[see Drug Interactions (7.6) ]</span>.

5.3 Falling Asleep During Activities of Daily Living and Somnolence Patients with Parkinson’s disease treated with ZELAPAR or other drugs increasing dopaminergic tone have reported falling asleep while engaged in activities of daily living, including the operation of motor vehicles, which sometimes resulted in accidents. Although many of these patients reported somnolence, some did not perceive warning signs, such as excessive drowsiness, and believed that they were alert immediately prior to the event. Some of these events have been reported as late as one year after initiation of treatment. It has been reported that falling asleep while engaged in activities of daily living always occurs in a setting of pre-existing somnolence, although patients may not give such a history. For this reason, prescribers should reassess patients for drowsiness or sleepiness especially since some of the events occur well after the start of treatment. Somnolence may occur in patients receiving ZELAPAR. There was an increased risk for somnolence in geriatric patients (≥65 years) vs. non-geriatric patients treated with ZELAPAR. Prescribers should also be aware that patients may not acknowledge drowsiness or sleepiness until directly questioned about drowsiness or sleepiness during specific activities. Patients should be advised to exercise caution while driving, operating machines, or working at heights during treatment with ZELAPAR. Patients who have already experienced somnolence and/or an episode of sudden sleep onset should not participate in these activities during treatment with ZELAPAR. Before initiating treatment with ZELAPAR, advise patients about the potential to develop drowsiness and specifically ask about factors that may increase this risk, such as concomitant sedating medications and the presence of sleep disorders. If a patient develops daytime sleepiness or episodes of falling asleep during activities that require active participation (e.g., conversations, eating, etc.), ZELAPAR should ordinarily be discontinued. If a decision is made to continue ZELAPAR, patients should be advised not to drive and to avoid other potentially dangerous activities. There is insufficient information to establish whether dose reduction will eliminate episodes of falling asleep while engaged in activities of daily living.

5.4 Hypotension/Orthostatic Hypotension Assessments of orthostatic (supine and standing) blood pressures at different times throughout the 12 week study period in two controlled trials showed that the frequency of orthostatic hypotension (&gt;20 mm Hg decrease in systolic blood pressure and/or &gt;10 mm Hg decrease in diastolic blood pressure) was greater with ZELAPAR treatment than with placebo treatment. Patients taking ZELAPAR were most likely to experience a decline in systolic and diastolic blood pressure at 8 weeks (2 weeks after initiating 2.5 mg ZELAPAR). At that time, the incidence of systolic orthostatic hypotension was about 21% in ZELAPAR-treated patients and 9% in placebo-treated patients. The incidence of diastolic orthostatic hypotension was about 12% in ZELAPAR-treated patients and about 4% in placebo-treated patients. Thus, it appears that there may be an increased risk for orthostatic hypotension in the period after increasing the daily dose of ZELAPAR from 1.25 to 2.5 mg. The incidence of orthostatic hypotension was higher in geriatric patients (≥65 years) than in non-geriatric patients. In the geriatric patients, orthostatic hypotension occurred in about 3% of ZELAPAR-treated patients compared to 0% of placebo-treated patients.

5.5 Dyskinesia ZELAPAR may potentiate dopaminergic side effects of levodopa and may cause dyskinesia or exacerbate preexisting dyskinesia. In controlled trials, the incidence of dyskinesia was 6% in ZELAPAR-treated patients and 3% in placebo-treated patients. Decreasing the dose of levodopa may lessen dyskinesia. The incidence of dyskinesia causing study discontinuation was greater on ZELAPAR than on placebo.

5.6 Hallucinations/Psychotic-Like Behavior In controlled trials, hallucination was reported by 4% of ZELAPAR-treated patients and 2% in placebo-treated patients. Hallucinations led to drug discontinuation and premature withdrawal from clinical trials in about 1% of ZELAPAR-treated patients, compared to no patient on placebo. Postmarketing reports indicate that patients may experience new or worsening mental status and behavioral changes, which may be severe, including psychotic-like behavior during ZELAPAR treatment or after starting or increasing the dose of ZELAPAR. Other drugs prescribed to improve the symptoms of Parkinson’s disease can have similar effects on thinking and behavior. This abnormal thinking and behavior can consist of one or more of a variety of manifestations including paranoid ideation, delusions, hallucinations, confusion, psychotic-like behavior, disorientation, aggressive behavior, agitation, and delirium. Patients with a major psychotic disorder should ordinarily not be treated with ZELAPAR because of the risk of exacerbating psychosis. In addition, certain medications used to treat psychosis may exacerbate the symptoms of Parkinson&apos;s disease and may decrease the effectiveness of ZELAPAR <span class="opacity-50 text-xs">[see Drug Interactions (7.8) ]</span>.

5.7 Impulse Control/Compulsive Behaviors Case reports suggest that patients can experience intense urges to gamble, increased sexual urges, intense urges to spend money, binge eating, and/or other intense urges, and the inability to control these urges while taking one or more of the medications, including ZELAPAR, that increase central dopaminergic tone and that are generally used for the treatment of Parkinson’s disease. In some cases, although not all, these urges were reported to have stopped when the dose was reduced or the medication was discontinued. Because patients may not recognize these behaviors as abnormal, it is important for prescribers to specifically ask patients or their caregivers about the development of new or increased gambling urges, sexual urges, uncontrolled spending, binge eating, or other urges while being treated with ZELAPAR. Physicians should consider dose reduction or stopping the medication if a patient develops such urges while taking ZELAPAR.

5.8 Withdrawal Emergent Hyperpyrexia and Confusion Although not reported with ZELAPAR in the clinical development program, a symptom complex resembling the neuroleptic malignant syndrome (characterized by elevated temperature, muscular rigidity, altered consciousness, and autonomic instability), with no other obvious etiology, has been reported in association with rapid dose reduction, withdrawal of, or changes in antiparkinsonian therapy.

5.9 Irritation of the Buccal Mucosa In the controlled clinical trials, periodic examinations of the tongue and oral mucosa were performed. At the end of the study, the frequency of mild oropharyngeal abnormality (e.g., swallowing pain, mouth pain, discrete areas of focal reddening, multiple foci of reddening, edema, and/or ulceration) in patients without similar abnormality at baseline was 10% in ZELAPAR-treated patients compared to 3% in placebo-treated patients.

5.10 Risk for Patients with Phenylketonuria Phenylalanine can be harmful to patients with phenylketonuria (PKU). ZELAPAR contains phenylalanine, a component of aspartame. Each ZELAPAR 1.25 mg tablet contains 1.25 mg phenylalanine. Patients taking the 2.5 mg dose of ZELAPAR will receive 2.5 mg phenylalanine. Before prescribing ZELAPAR to a patient with PKU, consider the combined daily amount of phenylalanine from all sources, including ZELAPAR .