Selegiline (Oral Route)

Selegiline is an orally administered medication that works to increase and extend the effects of the drug levodopa in a combined effort to slow the progress of Parkinson's disease.


When it is used as an orally administered drug, Selegiline acts as an inhibitor of monoamine oxidase and can be used as a treatment for depression. However, it is more well known for its use as a combination therapy with the drugs levodopa and carbidopa for its therapeutic value in treating Parkinson's disease. While not a cure, it has shown efficacy in slowing the advancement of the disease. Selegiline has a note of caution because it has been associated with a low rate of serum enzyme elevations during treatment, but has not yet shown a correlation with liver injury as a result of this effect. It is marketed under the brand names Eldepryl and Zelapar. It is a powerful prescription-only medication and should only be used as directed.

Selegiline functions by inhibiting monoamine oxidase (MAO) type B. This substance in the brain is a major enzyme in the production and movement of dopamine and levodopa metabolism. The resulting effect of the medication is to increase the levels and availability of levodopa in the system, leading to a significant increase in the duration of its resistance of Parkinson's symptoms as well as the strength of its effect. Its mechanism as an antidepressant is to inhibit dopamine reuptake, correcting a chemical imbalance that is contributing to the depressive behavior. When it was approved in 2006, Selegiline was the first MAO-B inhibitor that was approved for use in treating Parkinson's disease but only in combination with levodopa therapy. It is not recommended as a sole treatment of the disease or for other potential off-label purposes.

Conditions Treated

  • Parkinson's Disease
  • Depression

Type of Medication

  • Substituted phenethylamine

Side Effects

Like most medications, there are certain side effects that may come along with the use of Selegiline in addition to the intended use it is prescribed for. Some may be serious enough that additional medical attention is necessary when they arise. Check with your doctor if any of the following side effects occur as they can be indicative of a serious reaction to the medication.

The most common side effect is a series of uncontrolled or repetitive movements to include twitching and twisting of the limbs, face, tongue or lips.

Some of the less common reactions can be more serious and are listed below:

  • Blurred vision
  • Bruising
  • Chest pain
  • Convulsions
  • Decreased urine
  • Difficult or labored breathing
  • Difficulty with swallowing
  • Discouragement
  • Dizziness
  • Dry mouth
  • Feeling sad or empty
  • Headache
  • Increased thirst
  • Irregular heartbeat
  • Irritability
  • Large, flat, blue or purplish patches on the skin
  • Loss of appetite
  • Loss of interest or pleasure
  • Mood changes
  • Muscle pain or cramps
  • Nausea or vomiting
  • Nervousness
  • Numbness or tingling in the hands, feet, or lips
  • Pounding in the ears
  • Seeing, hearing, or feeling things that are not there
  • Shakiness and unsteady walk
  • Shakiness in the legs, arms, hands, or feet
  • Sleepiness or unusual drowsiness
  • Slow or fast heartbeat
  • Swelling or inflammation of the mouth
  • Tightness in the chest
  • Tiredness
  • Trouble concentrating
  • Trouble sleeping
  • Unsteadiness, trembling, or other problems with muscle control or coordination
  • Unusual tiredness or weakness

Although the incidence of the following side effects is not known, they are nonetheless very serious and should be reported.

  • Agitation
  • Diarrhea
  • Dizziness, faintness, or lightheadedness when getting up suddenly from a lying or sitting position
  • Fever
  • Overactive reflexes
  • Poor coordination
  • Restlessness
  • Shivering
  • Sweating
  • Talking or acting with excitement you cannot control

There are also specific side effects that are related to an overdose of Selegiline and emergency medical care should be sought if they occur.

Symptoms of an overdose include:

  • Agitation
  • Chest pain
  • Difficulty opening the mouth or lockjaw
  • Dizziness (severe) or fainting
  • Fast or irregular pulse (continuing)
  • High fever
  • High or low blood pressure
  • Severe spasm where the head and heels are bent backward and the body arched forward
  • Troubled breathing

In addition to these preceding serious side effects, there may be some routine side effects that are not normally a cause for concern. These may be as a result of the body adjusting to a new medication and will subside as the body gets used to the prescription. Your health care professional may have some remedies that will make these side effects easier to tolerate. If these symptoms are more intense than normal or are making recovery difficult consult with your physician about treatment options.

The most common of these routine side effects include the following:

  • Dry skin
  • Hives, itching, or skin rash
  • Itching, scaling, severe redness, soreness, or swelling of the skin
  • Runny nose
  • Sneezing
  • Stuffy nose
  • Trouble sleeping

Some of the less common routine side effects include the following:

  • Acid or sour stomach
  • Back pain
  • Belching
  • Bloated or full feeling
  • Body aches or pain
  • Congestion
  • Cough
  • Difficulty having a bowel movement (stool)
  • Difficulty with moving
  • Dryness or soreness of the throat
  • Excess air or gas in the stomach or intestines
  • Heartburn
  • Hoarseness
  • Indigestion
  • Joint pain
  • Leg cramps
  • Muscle aching or cramping
  • Muscle pains or stiffness
  • Passing gas
  • Stomach discomfort, upset, or pain
  • Swollen joints
  • Tender, swollen glands in the neck
  • Tooth problems
  • Voice changes

If you notice any other side effect not listed it may be indicative of a more serious condition or reaction to the medication. Contact your doctor regarding these symptoms immediately.


Doses of Selegiline can differ by the individual or by the condition for which they are prescribed. Follow all directions from your physician as these guidelines are only the manufacturer recommendations. The strength of the dose, amount of medication taken, or the amount of time that it is taken is also something that will need to be determined by the prescribing physician.

When used for the treatment of Parkinson's disease, the Selegiline capsules or tablets will be taken in 5mg doses twice daily. These doses are recommended to be taken at breakfast and lunch. This may vary if being used to treat a child, but in this case, dosage and schedule will be determined by a qualified pediatrician.

Oral disintegrating tablets may be used for patients who will have difficulty swallowing. These 1.25mg dosage tablets will be taken once per day before breakfast for the first 6 weeks. After that period the dosage may be increased up to 2.5mg daily. As with the capsules or tablets, a child's dose and schedule will be determined by a pediatrician.

If for any reason a dose is missed, it should be taken as soon as possible. If it is nearly the time to take the next dose the danger of a potential double-dose can be worse than missing a dose. It is advisable in that circumstance to skip to the next regularly scheduled dose at its appointed time.


Certain medications may have an adverse effect on the patient when used together. Some effects are serious enough that the drugs are strictly prohibited from being used at the same time as a result of the potential health risks. With that in mind, heed all of the following warnings for potential drug interactions. If it is necessary for you to use these prescriptions for an additional condition your doctor may reconsider the prescription of one or both of the medications. There may be a suitable replacement medication, or the dosages may be able to be adjusted to compensate for potential interactions. The following is not a complete list of all medications that may have an interaction with Selegiline, but they are the ones known to cause a significant reaction.

  • Amitriptyline
  • Amoxapine
  • Amphetamine
  • Apraclonidine
  • Atomoxetine
  • Benzphetamine
  • Brimonidine
  • Bupropion
  • Carbamazepine
  • Carbinoxamine
  • Citalopram
  • Clomipramine
  • Cyclobenzaprine
  • Cyproheptadine
  • Desipramine
  • Desvenlafaxine
  • Dexfenfluramine
  • Dexmethylphenidate
  • Dextroamphetamine
  • Dextromethorphan
  • Diethylpropion
  • Doxylamine
  • Duloxetine
  • Ephedrine
  • Escitalopram
  • Fenfluramine
  • Fluoxetine
  • Fluvoxamine
  • Furazolidone
  • Guanadrel
  • Guanethidine
  • Hydroxytryptophan
  • Imipramine
  • Iproniazid
  • Isocarboxazid
  • Isometheptene
  • Levomethadyl
  • Levomilnacipran
  • Linezolid
  • Lisdexamfetamine
  • Maprotiline
  • Mazindol
  • Meperidine
  • Methadone
  • Methamphetamine
  • Methotrimeprazine
  • Methyldopa
  • Methylene Blue
  • Methylphenidate
  • Milnacipran
  • Mirtazapine
  • Moclobemide
  • Nefopam
  • Nialamide
  • Nortriptyline
  • Opipramol
  • Paroxetine
  • Phendimetrazine
  • Phenelzine
  • Phenmetrazine
  • Phentermine
  • Phenylalanine
  • Phenylephrine
  • Phenylpropanolamine
  • Procarbazine
  • Propoxyphene
  • Protriptyline
  • Pseudoephedrine
  • Rasagiline
  • Reserpine
  • Safinamide
  • Selegiline
  • Sertraline
  • Sibutramine
  • St. John's Wort
  • Sumatriptan
  • Tapentadol
  • Tetrabenazine
  • Tramadol
  • Tranylcypromine
  • Trazodone
  • Trimipramine
  • Tryptophan
  • Venlafaxine
  • Vilazodone
  • Vortioxetine

The use of the following medications with Selegiline may be necessary in some cases, such as emergency medicine, but it is not recommended because of the potential for drug interactions. This may be mitigated by changing dosages or schedules.

  • Alizapride
  • Altretamine
  • Amineptine
  • Amisulpride
  • Amitriptylinoxide
  • Atropine
  • Bromperidol
  • Buprenorphine
  • Buspirone
  • Clovoxamine
  • Dibenzepin
  • Difenoxin
  • Diphenoxylate
  • Dolasetron
  • Domperidone
  • Dothiepin
  • Doxepin
  • Droperidol
  • Ethchlorvynol
  • Femoxetine
  • Fentanyl
  • Fluspirilene
  • Frovatriptan
  • Granisetron
  • Guarana
  • Haloperidol
  • Hydrocodone
  • Hydromorphone
  • Iobenguane I 123
  • Kava
  • Licorice
  • Lofepramine
  • Lorcaserin
  • Ma Huang
  • Mate
  • Melitracen
  • Mephentermine
  • Metaraminol
  • Metoclopramide
  • Metopimazine
  • Morphine
  • Morphine Sulfate Liposome
  • Naratriptan
  • Nefazodone
  • Oxycodone
  • Oxymetazoline
  • Palonosetron
  • Penfluridol
  • Pentazocine
  • Pimozide
  • Reboxetine
  • Sulpiride
  • Sultopride
  • Tianeptine
  • Tiapride
  • Tyrosine
  • Veralipride
  • Ziprasidone

Combining these drugs with Selegiline may have the quality of increasing the chance of side-effects caused by one or both of these medications, but they may still be prescribed if they represent the best chance for treating an affliction. They should only be prescribed with the greatest of caution and may need to be gradually introduced.

  • Acarbose
  • Chlorpropamide
  • Desogestrel
  • Dienogest
  • Dopamine
  • Drospirenone
  • Estradiol Cypionate
  • Estradiol Valerate
  • Ethinyl Estradiol
    Ethynodiol Diacetate
  • Etonogestrel
  • Ginseng
  • Glimepiride
  • Glipizide
  • Glyburide
  • Insulin
  • Insulin Aspart, Recombinant
  • Insulin Bovine
  • Insulin Degludec
  • Insulin Detemir
  • Insulin Glargine, Recombinant
  • Insulin Glulisine
  • Insulin Lispro, Recombinant
  • Levonorgestrel
  • Medroxyprogesterone Acetate
  • Mestranol
  • Metformin
  • Nateglinide
  • Norelgestromin
  • Norethindrone
  • Norgestimate
  • Norgestrel
  • Repaglinide
  • Tolazamide
  • Tolbutamide

There are certain other non-drug interactions that those who are prescribed Selegiline should be aware of prior to starting the medication. Eating certain foods and additives while taking Selegiline has been known to cause an adverse reaction. Such foods include Avocado, Bitter Orange, and foods containing Tyramine.

Other medical problems suffered by patients may affect the use of Selegiline for the treatment of Parkinson's. In some cases, the Selegiline may make these conditions worse. Inform your doctor if you currently have or have a history of the following conditions:

  • Dyskinesia
  • Hypertension
  • Mental illness
  • Psychotic episodes
  • Postural hypotension
  • Kidney disease
  • Liver disease
  • Phenylketonuria(PKU)


It is very important that your doctor checks your progress at regular visits to allow for changes in your dose and to check for any unwanted effects. Selegiline should not be used in conjunction with painkillers like meperidine or MAO inhibitors (MAOI). There needs to be a full two-week gap between taking these medications and starting a Selegiline regimen. Failure to observe this may lead to the most severe of possible medication interactions. Some of the mental side effects can include confusion, agitation, and restlessness. Physical symptoms caused by this interaction include extremely high blood pressure or body temperature often accompanied by problems of the stomach or intestinal tract. The reaction has also been known to cause spasms and convulsions. These reactions or those like them may also be experienced when taking many over-the-counter medications and unapproved supplements, so all such medications or herbal remedies should be cleared by a physician before using Selegiline.

A serious concern for those taking Selegiline is a condition called serotonin syndrome that is caused by an adverse reaction to a wide variety of medications including common antidepressant medications and MAO inhibitors. The harsh symptoms of serotonin syndrome include:

  • Anxiety
  • Restlessness
  • Fast heartbeat
  • Fever
  • Sweating
  • Muscle spasms
  • Twitching
  • Nausea
  • Vomiting
  • Diarrhea
  • Hallucinations

The use of selegiline may need to come with certain dietary restrictions when the medicine is taken. At small doses under 10mg daily there are no restrictions that need to be observed, but there is a danger of sudden high blood pressure when the patient takes higher doses. When a higher dose is necessary for the treatment of Parkinson's disease please observe the following dietary restrictions.

Avoid foods that have a high content of tyramine, an ingredient commonly found in foods flavored through a fermentation process. If you have any doubt about a food that you enjoy ask your physician if it may contain tyramine. While the following is not a complete list, it contains the most common foods:

  • Cheeses
  • Fava Beans
  • Sausages
  • Sauerkraut
  • Certain overripe fruit
  • Pickled or smoked meat
  • Yeast
  • Alcholic beverages
  • Alchohol-free beer and wine

In addition to this restriction, caffeine is to be avoided in large amounts. This means that most sodas, chocolate, tea, and coffee should not be regularly consumed while taking Selegiline. This also includes many of the most popular commercial products that are used for stimulation and wakefulness. This should also be observed for at least two weeks after a patient stops taking Selegiline, as the drug still may remain in the system to interact with the prohibited dietary substances.

Due to a large number of medicines that interact poorly with Selegiline, it is crucial that any over-the-counter medication use is reported to the prescribing physician. This includes such remedies as cough drops and throat sprays. If the patient experiences difficulty sleeping while using Selegiline seek medical help rather than using an over-the-counter or herbal remedy.

There are certain reactions that should prompt an immediate call for emergency medicine when using Selegiline. If the patient experiences a severe headache, a stiffness of the neck, chest pains, irregular heartbeat, or nausea accompanied by vomiting this could be indicative of a more serious and potentially fatal condition.

Selegiline has been known to make those who take it exceptionally drowsy and may result in episodes of falling asleep even while performing a task. Those taking Selegiline should not drive or operate machinery while using the medication until they are aware of to what degree they will be affected by it. Patients have also commonly experienced difficulties when getting up from a seated or lying position, including dizziness and fainting spells. While getting up slowly may help reduce this feeling of lightheadedness, a doctor should be informed if it is too long in duration or gets worse with time.

Selegiline is a harsh medication that can result in some issues with the upper digestive system. Inform a doctor immediately if any difficulty in swallowing is experienced or if there are any indications of pain, swelling, redness, or sores in the mouth or throat area. It also has been known to cause dryness of the mouth. While this has temporary remedies such as chewing gum or saliva substitutes, if it is experienced for more than two weeks is may prompt a visit to the dentist. Dry mouth conditions can increase the chances of gum disease, tooth decay, and certain fungal infections.

There is a risk of radically changed behavior that comes with using Selegiline, one of the most common of which is a significant increase in impulsivity and difficulty in self-control. If sudden addictive behaviors including increased gambling or sex drive are noticed they may be caused by the medication. There is also a risk of chemical dependence and withdrawal associated with this medication and it is dangerous to suddenly stop its use. Patients should only stop taking Selegiline under the supervision of a physician, who will gradually reduce the dose before stopping the regimen completely.

There are also special considerations in place for older people taking this medication. When taking Selegiline it is important to regularly have skin examined for spots and blemishes. Unusual brown, black, or red spots on the skin may be indicative of a skin cancer called melanoma. If any such spots are seen have them examined by a physician. Elderly patients also are more likely to have certain age-related medical conditions that may require additional caution when prescribing Selegiline.


This medication is subject to many of the same guidelines that are good practice for most medications in pill or capsule form. It is recommended that the medication is stored in a closed container in a secure location away from the reach of children or pets. It should also be isolated from moisture, excessive heat, and direct sunlight. Care should be taken to keep it from freezing. Selegiline should not be kept or maintained in a patient's care if it is no longer prescribed or if it has passed its expiration date. If this is the case, the medication should be disposed of in adherence to local guidelines regarding the disposal of medical waste. If you have any questions regarding this you can ask your doctor or a pharmacist. Take care to reorder medications before they run out or expire if this medication is still prescribed.


Selegiline is an effective drug in the prevention of the breakdown of a chemical messenger called Dopamine. Parkinson's disease is characterized by extremely low levels of dopamine in the brain of the patient. A combination therapy of Selegiline used together with other associated medications may represent a patient's best chance to maintain motor function while suffering from Parkinson's. It may also be of value in the treatment of depression but is not intended to be used to treat both conditions in a patient. Because of the nature of this disease, it may not be possible for self-administration of the medication especially as the disease advances in severity. A gradual increase in the strength of the prescription may be necessary to continue to have the desired effects, but may eventually realize diminishing returns.

While it is true that Selegiline can be an effective combination medication for the treatment of Parkinson's disease, it is a potent medication with a bevy of potentially debilitating side-effects. The truth is that Parkinson's is such a debilitating disease in itself that any possible relief from the ravages of the disease is considered worth the potential risks posed by Selegiline. If it is prescribed as a course of treatment for Parkinson's it is important that it be prescribed in the correct proportion to treatment with levodopa and that the progress of the disease be carefully and closely monitored by a doctor during the course of the treatment to ensure that it is having the desired effect without causing more damage via side effects or drug interactions.


Last Reviewed:
January 28, 2018
Last Updated:
January 27, 2018
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