What to Know About Minocin (Minocycline)

Minocin (minocycline) is a second generation tetracycline antibiotic. It is used to treat gram-negative and gram-positive bacterial infections. It works to treat infections by preventing the growth and spread of bacteria. It is taken in capsule form.

Minocycline is currently the most effective tetracycline derivative at providing neuroprotection. It has anti-inflammatory effects and has been used off-label in treating rheumatoid arthritis.

This antibiotic does not work against the common cold and other viruses. It's important to note that using antibiotics when they are not needed increases your risk of getting an infection later that resists antibiotic treatment.

Uses

Minocycline is a tetracycline antibiotic that is used to treat bacterial infections including:

• Urinary tract infections
• Respiratory infections
• Severe acne
• Chlamydia
• Tick fever
• Plague
• Tularemia

This antibiotic is considered a second line drug for those individuals with a penicillin allergy. For that reason it can be used to treat:

• Gonorrhea
• Syphilis
• Anthrax
• Food poisoning

Off-Label Uses

Because of its anti-inflammatory properties, minocycline is sometimes used to treat mild rheumatoid arthritis (RA). In the past, it was considered for new-onset RA. However, the 2015 American College of Rheumatology guidelines for treating RA dropped minocycline due to it rarely being used and there being no new studies on it.

Currently, there is some research that indicates minocycline can be used off label for schizophrenia, psychotic symptoms, and bipolar depression. Additional studies are being conducted to further examine the effectiveness of minocycline in treating neurologic disorders such as :

• Stroke
• Multiple sclerosis
• Spinal-cord injury
• Parkinson’s disease
• Huntington’s disease
• Amyotrophic lateral sclerosis

Before Taking

It’s important to discuss with your medical provider all allergies to medications prior to taking a minocycline. Do not use this medicine if you are allergic to minocycline or tetracycline antibiotics. Other precautions and contraindications include:

• Tell your healthcare provider and pharmacist what other prescription and nonprescription medications, vitamins, nutritional supplements, and herbal products you are taking or plan to take.
• Discuss with your healthcare provider if you are taking any of the following medications: anticoagulants, bromocriptine, cabergoline, dihydroergotamine, ergoloid mesylates, ergonovine, ergotamine, methylergonovine, and penicillin.
• Tell your healthcare provider if you have or have ever had asthma, lupus, intracranial hypertension cerebri, kidney or liver disease.
• Discuss with your healthcare provider if you are currently on oral contraceptives and sexually active. Minocycline may decrease the effectiveness of hormonal contraceptives.
• Discuss with your healthcare provider if you are pregnant or actively trying to become pregnant. Minocycline can harm the fetus.

Talk to your healthcare provider about all medications, supplements, and vitamins that you currently take. While some drugs pose minor interaction risks, others may outright contraindicate use or prompt careful consideration as to whether the pros of treatment outweigh the cons in your case.

Other Tetracycline Antibiotics

Minocycline is a tetracycline antibiotic. Other tetracycline antibiotics include:

• Lymecycline
• Methacycline
• Rolitetracycline
• Doxycycline
• Oxytetracycline
• Demeclocycline
• Tigecycline
• Chlortetracycline
• Eravacycline
• Omadacycline
• Sarecycline

Dosage

All listed dosages are according to the drug manufacturer. Check your prescription and talk to your healthcare provider to make sure you are taking the right dose for you. 

Adults: General dosing guidelines are 200 milligrams (mg) initially followed by 100 mg every 12 hours or take 100-200 mg initially followed by 50 mg capsule four times daily.

Specific dosage for certain infections include:

• Uncomplicated gonococcal infections other than urethritis and anorectal infections in men: 200 mg initially, followed by 100 mg every 12 hours for a minimum of 4 days
• Uncomplicated gonococcal urethritis in men: 100 mg every 12 hours for 5 days
• Syphilis: 200 mg initially followed by 100 mg every 12 hours for 10 to 15 days

Pediatric patients above 8 years old: 4 mg/kg initially followed by 2 mg/kg every 12 hours

How to Take and Store

Exact dosage and frequency will be determined by your healthcare provider but the FDA suggests:

• Comes in capsule or tablet form.
• May be taken with or without food.
• Take with a full glass of liquid to decrease gastrointestinal upset.
• Take exactly as directed even if feeling better. Finish the entire prescription.
• Take a missed dose as soon as you think about it.
• Take minocycline exactly as directed.
• Do not take two doses at the same time or extra doses.

Follow these guidelines for storage:

• Store in the airtight original container
• Protect from light, extreme heat, and extreme cold
• Keep away from moisture (i.e. bathroom)
• Keep away from children.
• Dispose of unused medication through a pharmacy or a medication disposal company.
• Once expired, dispose of medication.

Side Effects

As with all medications, there are possible side effects you may experience while taking minocycline. Common side effects include:

• Nausea
• Vomiting
• Diarrhea
• Itching of the rectum or vagina
• Changes in color of skin, scars, nails, teeth or gums.
• Changes in color of tears or urine
• Tinnitus (ringing in your ears)
• Hair loss
• Xerostomia (dry mouth)
• Sore or irritated throat
• Inflammation of the end of the penis
• Muscle pain
• Mood changes
• Numbness, tingling, or prickling sensation on skin

While the aforementioned side effects are relatively common, if any of the symptoms are severe or do not go away it is important to contact your healthcare provider immediately.

Even though these may be rare, minocycline does have side effects that require immediate medical attention as they can be life-threatening:

• Headache
• Blurred vision, seeing double, or loss of vision
• Rash
• Urticaria (hives)
• Peeling or blistering skin
• Angioedema (swelling of the face, throat, tongue, lips, and eyes)
• Difficulty breathing or swallowing
• Shortness of breath
• Yellowing of the skin or eyes
• Dark-colored urine
• Light-colored bowel movements
• Extreme fatigue
• Confusion
• Bloody urine
• Joint pain, stiffness or swelling. Minocycline has been associated with a drug-induced lupus where patients may develop joint pain
• Swollen lymph nodes
• Unusual bleeding or bruising
• Decreased urination
• A return of fever, sore throat, chills, or other signs of infection
• Watery or bloody stools, stomach cramps, or fever during treatment or for up to two or more months after stopping treatment
• Seizures
• Chest pain or arrhythmias

Warnings and Interactions

Be aware of these:

• Minocycline can make birth control pills less effective. Alternative means of birth control should be used while on this medication to avoid pregnancy.
• Minocycline crosses the placenta and should be used with extreme caution in people who are pregnant. Do not take if pregnant, planning on getting pregnant, or breastfeeding. Minocycline can cause fetal harm and/or demise.
• Contraindicated in children under the age of 8. Minocycline can cause permanent yellowing or graying of the teeth in children younger than 8 years old.
• When taken in combination with Plaquenil (hydroxychloroquine), a medication used to treat lupus and rheumatoid arthritis, patients may develop areas of increased skin pigmentation.