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Loniten Side Effects

Generic name: minoxidil

Medically reviewed by Drugs.com. Last updated on Aug 20, 2023.

Note: This document contains side effect information about minoxidil. Some dosage forms listed on this page may not apply to the brand name Loniten.

Applies to minoxidil: oral tablet.

Warning

Oral route (Tablet)

Minoxidil can cause pericardial effusion, occasionally progressing to tamponade, and angina pectoris may be exacerbated. Minoxidil should be reserved for hypertensive patients who do not respond adequately to maximum therapeutic doses of a diuretic and two other antihypertensive agents. Minoxidil must be administered under close supervision, usually concomitantly with therapeutic doses of a beta-adrenergic blocking agent to prevent tachycardia and increased myocardial workload. It must also usually be given with a diuretic, frequently one acting in the ascending limb of the loop of Henle, to prevent serious fluid accumulation. Patients with malignant hypertension and those already receiving guanethidine should be hospitalized when minoxidil is first administered so that they can be monitored to avoid too rapid, or large orthostatic, decreases in blood pressure.

Serious side effects of Loniten

Along with its needed effects, minoxidil (the active ingredient contained in Loniten) 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 minoxidil:

More common

Less common

Check with your doctor as soon as possible if any of the following side effects occur while taking minoxidil:

More common

Less common

Rare

Other side effects of Loniten

Some side effects of minoxidil 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:

More common

Less common or rare

This medicine causes a temporary increase in hair growth in most people. Hair may grow longer and darker in both men and women. This may first be noticed on the face several weeks after you start taking minoxidil. Later, new hair growth may be noticed on the back, arms, legs, and scalp. Talk to your doctor about shaving or using a hair remover during this time. After treatment with minoxidil has ended, the hair will stop growing, although it may take several months for the new hair growth to go away.

For Healthcare Professionals

Applies to minoxidil: compounding powder, oral tablet.

General

Most patients receiving have experienced a decrease of preexisting adverse medical events attributable to their disease or previous therapy. The most frequently reported side effects were hypertrichosis, tachycardia, pericarditis, and an abnormal ECG.[Ref]

Cardiovascular

Very common (10% or more): ECG abnormal (up to 60%), tachycardia, pericarditis

Common (1% to 10%): Pericardial effusion, tamponade

Frequency not reported: Angina pectoris, hypotension[Ref]

Dermatologic

Very common (10% or more): Hypertrichosis (up to 80%), hair color changed

Rare (less than 0.1%): Stevens-Johnson syndrome, dermatitis bullous, rash

Frequency not reported: Toxic epidermal necrolysis[Ref]

Elongation, thickening, and enhanced pigmentation of fine body hair has been reported in about 80% of patients. This usually develops within 3 to 6 weeks after beginning therapy and is first noticed on the temples, between the eyebrows, between the hairline and the eyebrows, or in the sideburn area of the upper lateral cheek, and eventually extending to the back, arms, legs, and scalp. Upon discontinuation of this drug, new hair growth stops, however, 1 to 6 months may be required for restoration to pretreatment appearance. Endocrine abnormalities have not been found to explain the abnormal hair growth.[Ref]

Gastrointestinal

Common (1% to 10%): Gastrointestinal disorder

Frequency not reported: Nausea/vomiting, gastrointestinal intolerance[Ref]

Hematologic

Rare (less than 0.1%): Leukopenia, thrombocytopenia

Frequency not reported: Hematocrit decreased, hemoglobin decreased, erythrocyte count decreased

Metabolic

Common (1% to 10%): Fluid retention[Ref]

Genitourinary

Uncommon (0.1% to 1%): Breast tenderness[Ref]

Respiratory

Uncommon (0.1% to 1%): Pleural effusion

Other

Common (1% to 10%): Edema

Frequency not reported: Peripheral edema, weight gain, blood creatinine increased, blood urea increased, alkaline phosphatase increased[Ref]

Frequently asked questions

References

1. Product Information. Loniten (minoxidil). Pharmacia and Upjohn. 2002;PROD.

2. Cerner Multum, Inc. UK Summary of Product Characteristics.

3. Cerner Multum, Inc. Australian Product Information.

Further information

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.

Some side effects may not be reported. You may report them to the FDA.