Midodrine

What Are the Most Common and Serious Side Effects of Midodrine Hydrochloride?

While midodrine hydrochloride may alleviate your condition, it is not without side effects. Talk to your doctor about the various side effects and report any unusual problems to the FDA at 1-800-FDA-1088.

Common Side Effects:

Some of the more common side effects of midodrine hydrochloride are chills, goose bumps, frequent urination, blurred vision, and burning, itching, or prickling of the scalp. Other common side effects may include an awareness of the heart pounding in the ears or a headache.

Less Common Side Effects:

While less common, patients taking midodrine hydrochloride are known to experience confusion, dry mouth, flushing, skin rash, anxiety/nervousness, and headache or a feeling of pressure in the head.

Rare:

Other symptoms like backache, canker sores, increased dizziness or drowsiness, dry skin, or leg cramps, as well as the following:

• Trouble sleeping
• Gas, heartburn, or nausea

Contact your doctor immediately if you experience a slow heartbeat, an unusual feeling in your chest, pressure/fullness in the head, confusion, anxiety, weakness, vision problems or fainting. Get in touch with your doctor or call 911 right away if you have signs of an allergic reaction such as rash, itching/swelling, especially of the face, tongue and throat, severe dizziness, or trouble breathing.

Stop taking midodrine hydrochloride immediately if you experience the following signs of high blood pressure while lying down:

• Pounding heartbeat or pounding in the ears
• Headache
• Blurred vision

Do Other Drugs Affect the Way Midodrine Hydrochloride Works?

Other medications may impact the way midodrine hydrochloride works and/or increase the risk of side effects. Be sure to provide your doctor with an updated list of all the medications you are taking, including over-the-counter items like vitamins and herbal products. In addition, do not make any dosage adjustments or quit taking any drug without your doctor’s approval.

Be sure to let you doctor know if you are using adrenaline-like drugs such asephedrine,phenylephrine,pseudoephedrine, or alpha blockers like doxazosin (Cardura), prazosin (Minipress) and terazosin (Hytrin).

Other drugs that could interact with midodrine hydrochloride include those that control high blood pressure or psychiatric medications, particularly some antidepressants and antipsychotic medicines.

Tell your doctor if you are using beta-blockers like atenolol (Tenormin), metoprolol (Lopressor),digoxin (Lanoxin), or ergot alkaloids such asdihydroergotamine (Migranal) and ergotamine (Ergomar).

If your low blood pressure medication includes fludrocortisone (Florinef), be sure you monitor yourself closely, especially if you are lying down. Using this drug together with midodrine hydrochloride will make you more likely to develop high blood pressure when lying down.

In addition, pay close attention to the labels on cough and cold products, diet aids, and non-steroidal anti-inflammatory drugs (NSAIDS) such as ibuprofen and naproxen since they might contain ingredients that could raise your blood pressure.

Should I Avoid Any Food, Drink or Activity While Taking Midodrine Hydrochloride?

If you are using midodrine hydrochloride, it’s recommended that you get up slowly from sitting or lying down to help reduce dizziness. In addition, limit your use of alcoholic beverages.

Midodrine hydrochloride may make you dizzy, drowsy, or cause blurred vision, so do not drive, use machinery or engage in activities that require you to be alert or have clear vision until you know if you can do so safely.

If you are going to have surgery, it’s important to let your doctor know you are using this medication.

Midodrine is a prescription medication used to treat orthostatic hypotension (OH). OH results in dizziness, lightheadedness, or even fainting after standing from a sitting or lying down position.

This medication may be prescribed for other uses. Ask your doctor or pharmacist for more information.

In the U.S.

• Orvaten
• Proamatine

Available Dosage Forms:

• Tablet

Therapeutic Class: Vasopressor

Pharmacologic Class: Sympathomimetic

Midodrine is used to treat low blood pressure (hypotension). It works by stimulating nerve endings in blood vessels, causing the blood vessels to tighten. As a result, blood pressure is increased.

midodrine is available only with your doctor's prescription.

The last dose of midodrine should not be taken after the evening meal or less than 3 to 4 hours before bedtime because high blood pressure upon lying down (supine hypertension) can occur, which can cause blurred vision, headaches, and pounding in the ears while lying down after taking midodrine.

Also, midodrine should not be taken if you will be lying down for any length of time.

Dosing

The dose of midodrine will be different for different patients. Follow your doctor's orders or the directions on the label. The following information includes only the average doses of midodrine. If your dose is different, do not change it unless your doctor tells you to do so.

The amount of medicine that you take depends on the strength of the medicine. Also, the number of doses you take each day, the time allowed between doses, and the length of time you take the medicine depend on the medical problem for which you are using the medicine.

• For oral dosage form (tablets):
  • For low blood pressure:
    • Adults—10 milligrams (mg) three times a day in approximately 4-hour intervals during daytime hours: shortly before or upon rising in the morning, at midday, and in the late afternoon (not later than 6 p.m.). Your doctor may increase your dose if needed.
    • Children—Use and dose must be determined by your doctor.

Missed Dose

If you miss a dose of midodrine, take it as soon as possible. However, if it is almost time for your next dose, skip the missed dose and go back to your regular dosing schedule. Do not double doses.

Storage

Store the medicine in a closed container at room temperature, away from heat, moisture, and direct light. Keep from freezing.

Keep out of the reach of children.

Do not keep outdated medicine or medicine no longer needed.

Ask your healthcare professional how you should dispose of any medicine you do not use.

The most frequent adverse reactions seen in controlled trials were supine and sitting hypertension; paresthesia and pruritus, mainly of the scalp; goosebumps; chills; urinary urge; urinary retention and urinary frequency.

The frequency of these events in a 3-week placebo-controlled trial is shown in the following table:

Less frequent adverse reactions were headache; feeling of pressure/fullness in the head; vasodilation/flushing face; confusion/thinking abnormality; dry mouth; nervousness/anxiety and rash. Other adverse reactions that occurred rarely were visual field defect; dizziness; skin hyperesthesia; insomnia; somnolence; erythema multiforme; canker sore; dry skin; dysuria; impaired urination; asthenia; backache; pyrosis; nausea; gastrointestinal distress; flatulence and leg cramps.

The most potentially serious adverse reaction associated with Midodrine therapy is supine hypertension. The feelings of paresthesia, pruritus, piloerection and chills are pilomotor reactions associated with the action of Midodrine on the alpha-adrenergic receptors of the hair follicles. Feelings of urinary urgency, retention and frequency are associated with the action of Midodrine on the alpha-receptors of the bladder neck.

Midodrine hydrochloride tablets, USP are supplied as 2.5 mg, 5 mg and 10 mg tablets for oral administration.

The 2.5 mg tablet is a white, round, uncoated tablet, scored on one side with "US" above and "2.5" below the score and "211" on the other side. They are supplied as follows:

The 5 mg tablet is a pink, round, uncoated tablet, scored on one side with "US" above and "5" below the score and "212" on the other side. They are supplied as follows:

The 10 mg tablet is a purple, round, uncoated tablet, scored on one side with "US" above and "10" below the score and "213" on the other side. They are supplied as follows:

Store at 20° to 25°C (68° to 77°F); excursions permitted to 15° to 30°C (59° to 86°F) [See USP Controlled Room Temperature].

Manufactured by
UPSHER-SMITH LABORATORIES, LLC
Maple Grove, MN 55369

Revised 0717

• Midodrine HCl
• Midodrine Hydrochloride
• ProAmatine

2 to 3 hours

Half-Life Elimination

Desglymidodrine: ~3 to 4 hours; Midodrine: 25 minutes

Protein Binding

Minimal

Orthostatic hypotension: 2.5 mg 3 times daily; gradually increase as tolerated.

Hemodialysis: Dialyzable

Alpha1-Blockers: May diminish the vasoconstricting effect of Alpha1-Agonists. Similarly, Alpha1-Agonists may antagonize Alpha1-Blocker vasodilation. Monitor therapy

AtoMOXetine: May enhance the hypertensive effect of Sympathomimetics. AtoMOXetine may enhance the tachycardic effect of Sympathomimetics. Monitor therapy

Benzylpenicilloyl Polylysine: Alpha1-Agonists may diminish the diagnostic effect of Benzylpenicilloyl Polylysine. Management: Consider use of a histamine skin test as a positive control to assess a patient's ability to mount a wheal and flare response. Consider therapy modification

Beta-Blockers: May enhance the bradycardic effect of Midodrine. Monitor therapy

Calcium Channel Blockers (Nondihydropyridine): May enhance the bradycardic effect of Midodrine. Monitor therapy

Cannabinoid-Containing Products: May enhance the tachycardic effect of Sympathomimetics. Exceptions: Cannabidiol. Monitor therapy

Cardiac Glycosides: May enhance the bradycardic effect of Midodrine. Monitor therapy

Cocaine: May enhance the hypertensive effect of Sympathomimetics. Management: Consider alternatives to use of this combination when possible. Monitor closely for substantially increased blood pressure or heart rate and for any evidence of myocardial ischemia with concurrent use. Consider therapy modification

Doxofylline: Sympathomimetics may enhance the adverse/toxic effect of Doxofylline. Monitor therapy

Droxidopa: Midodrine may enhance the hypertensive effect of Droxidopa. Monitor therapy

Ergot Derivatives: May enhance the hypertensive effect of Alpha1-Agonists. Ergot Derivatives may enhance the vasoconstricting effect of Alpha1-Agonists. Exceptions: Ergoloid Mesylates; Nicergoline. Avoid combination

Guanethidine: May enhance the arrhythmogenic effect of Sympathomimetics. Guanethidine may enhance the hypertensive effect of Sympathomimetics. Monitor therapy

Iobenguane I 123: Sympathomimetics may diminish the therapeutic effect of Iobenguane I 123. Avoid combination

Linezolid: May enhance the hypertensive effect of Sympathomimetics. Management: Reduce initial doses of sympathomimetic agents, and closely monitor for enhanced pressor response, in patients receiving linezolid. Specific dose adjustment recommendations are not presently available. Consider therapy modification

MAO Inhibitors: May enhance the hypertensive effect of Alpha1-Agonists. While linezolid is expected to interact via this mechanism, management recommendations differ from other monoamine oxidase inhibitors. Refer to linezolid specific monographs for details. Exceptions: Linezolid; Tedizolid. Avoid combination

Sympathomimetics: May enhance the adverse/toxic effect of other Sympathomimetics. Monitor therapy

Tedizolid: May enhance the hypertensive effect of Sympathomimetics. Tedizolid may enhance the tachycardic effect of Sympathomimetics. Monitor therapy

Tricyclic Antidepressants: May enhance the vasopressor effect of Alpha1-Agonists. Tricyclic Antidepressants may diminish the vasopressor effect of Alpha1-Agonists. Monitor therapy

Concerns related to adverse effects:

• Bradycardia: May slow heart rate primarily due to vagal reflex. Use caution when administered concurrently with negative chronotropes (eg, digoxin, beta blockers). Discontinue use if signs or symptoms of bradycardia occur.

• Hypertension: May cause supine hypertension; discontinue use immediately if supine hypertension persists. Use with caution when administered concurrently with vasoconstrictors (eg, phenylephrine, ephedrine, dihydroergotamine, phenylpropanolamine, pseudoephedrine). Use is not recommended in patients with initial supine systolic pressure >180 mm Hg. Due to marked elevation of supine blood pressure (BP greater than 200 mm Hg systolic), use in patients whose lives are considerably impaired despite standard clinical care, including nonpharmacologic treatment (such as support stockings), fluid expansion, and lifestyle alterations. Supine and sitting blood pressure should be monitored.

Disease-related concerns:

• Diabetes: Use with caution in patients with diabetes mellitus.

• Hepatic impairment: Use with caution in patients with hepatic impairment; has not been studied.

• Renal impairment: Desglymidodrine, the active metabolite, is primarily renally excreted; assess renal function prior to initial dose; use with caution in patients with renal impairment (has not been studied) and initiate with a reduced dose; contraindicated in patients with acute renal failure.

• Visual problems: Use with caution in patients with visual problems, especially if receiving fludrocortisone.

Other warnings/precautions:

• Appropriate use: [U.S. Boxed Warning]: Indicated for patients for whom orthostatic hypotension significantly impairs their daily life despite standard clinical care. Use is not recommended with supine hypertension. Continue therapy only in patients who appear to attain symptomatic improvement during initial treatment.

Applies to midodrine: oral tablet

Along with its needed effects, midodrine may cause some unwanted effects. Although not all of these side effects may occur, if they do occur they may need medical attention.

Check with your doctor immediately if any of the following side effects occur while taking midodrine:

• Blurred vision
• cardiac awareness
• headache
• pounding in the ears

• Fainting
• increased dizziness
• slow pulse

Some side effects of midodrine may occur that usually do not need medical attention. These side effects may go away during treatment as your body adjusts to the medicine. Also, your health care professional may be able to tell you about ways to prevent or reduce some of these side effects. Check with your health care professional if any of the following side effects continue or are bothersome or if you have any questions about them:

• Burning, itching, or prickling of the scalp
• chills
• goosebumps
• urinary frequency, retention, or urgency

• Anxiety or nervousness
• confusion
• dry mouth
• flushing
• headache or feeling of pressure in the head
• skin rash

• Backache
• canker sores
• dizziness
• drowsiness
• dry skin
• leg cramps
• pain or sensitivity of the skin to touch
• stomach problems such as gas, heartburn, or nausea
• trouble seeing
• trouble with sleeping
• weakness

US BOXED WARNING:
-SUPINE HYPERTENSION: Because this drug can cause marked elevation of supine blood pressure, it should be used in patients whose lives are considerably impaired despite standard clinical care. The indication for this drug in the treatment of symptomatic orthostatic hypotension is based primarily on a change in a surrogate marker of effectiveness, an increase in systolic blood pressure measured one minute after standing, a surrogate marker considered likely to correspond to a clinical benefit. At present, however, clinical benefits of this drug, principally improved ability to carry out activities of daily living, have not been verified.

Safety and efficacy have not been established in patients younger than 18 years.

Consult WARNINGS section for additional precautions.

Use should be avoided; otherwise, caution is recommended. Excreted into human milk: Unknown Excreted into animal milk: Data not available Comments: The effects in the nursing infant are unknown.