WARNING

Isoniazid is a medication commonly used to treat tuberculosis (TB). While it is generally effective, there are potential risks and side effects associated with its use. Here’s a brief overview of some of the risks of taking Isoniazid:

• Hepatotoxicity: Isoniazid can cause liver damage in some individuals. Regular monitoring of liver function is often recommended during treatment.
• Peripheral Neuropathy: Long-term use of Isoniazid, particularly in individuals with poor nutrition or certain pre-existing conditions, may lead to peripheral neuropathy, which is damage to the nerves in the extremities.
• Allergic Reactions: Some people may experience allergic reactions to Isoniazid, which can range from mild skin rashes to severe reactions like Stevens-Johnson syndrome.
• Drug Interactions: Isoniazid can interact with other medications, potentially affecting their efficacy or increasing the risk of side effects. It’s important to inform your healthcare provider about all medications you are taking.
• Metabolic Effects: Isoniazid may lead to changes in blood sugar levels, which could be of concern in individuals with diabetes.
• Psychiatric Effects: Rarely, Isoniazid has been associated with psychiatric side effects, such as psychosis and depression.
• Peripheral Arthralgia: Some individuals may experience joint pain as a side effect of Isoniazid.

It’s crucial to take Isoniazid under the supervision of a healthcare professional who can monitor for these potential risks and adjust the treatment plan if necessary. Patients should report any unusual symptoms or side effects promptly to their healthcare provider. The benefits of treating tuberculosis with Isoniazid often outweigh the risks, especially when the medication is prescribed and monitored appropriately.

Why is this medication prescribed?

Isoniazid is prescribed primarily for the treatment of tuberculosis (TB). It is a key component of the standard multi-drug therapy used to treat both latent TB infection and active TB disease. Isoniazid works by inhibiting the growth of the bacteria responsible for tuberculosis, particularly Mycobacterium tuberculosis.

Indications for Isoniazid use:

• Active Tuberculosis: Isoniazid is commonly used in combination with other anti-TB medications to treat active tuberculosis.
• Latent Tuberculosis Infection (LTBI): It is also used to prevent the development of active TB in individuals who have been exposed to the bacteria and have a latent infection. This is often referred to as preventive therapy.

How should this medicine be used?

The dosage and duration of isoniazid treatment can vary based on the specific circumstances and the form of TB being treated. It’s important to follow your healthcare provider’s instructions carefully. Here are some general guidelines:

• Active TB Treatment:
  • Isoniazid is typically prescribed in combination with other anti-TB drugs.
  • The standard treatment regimen for active TB often involves a combination of isoniazid, rifampin, pyrazinamide, and ethambutol.
  • The duration of treatment can range from 6 months to more extended periods, depending on the specific case.
• Latent TB Infection (Preventive Therapy):
  • For individuals with latent TB infection, isoniazid is often prescribed as a single drug.
  • The typical duration of preventive therapy is 9 months, although shorter regimens may be considered in certain situations.

General guidelines for taking Isoniazid:

• Take as Prescribed: Follow your healthcare provider’s instructions regarding the dosage and duration of treatment.
• Take on an Empty Stomach: Isoniazid is usually taken on an empty stomach, either one hour before or two hours after meals.
• Avoid Alcohol: Alcohol consumption should be minimized or avoided during isoniazid treatment, as it can increase the risk of liver toxicity.
• Vitamin B6 (Pyridoxine) Supplementation: Your healthcare provider may recommend vitamin B6 supplements to help prevent peripheral neuropathy, a potential side effect.
• Regular Monitoring: Your healthcare provider will likely monitor your liver function through blood tests during the course of treatment.

It’s essential to attend all follow-up appointments and notify your healthcare provider if you experience any side effects or have concerns about your treatment. Do not stop taking isoniazid or change the dosage without consulting your healthcare provider, even if you start to feel better. Stopping treatment prematurely can lead to treatment failure and the development of drug-resistant TB.

Other uses for this medicine

While isoniazid (INH) is primarily used for the treatment of tuberculosis (TB), it may also be employed for other medical conditions in certain situations. Some of these include:

• Latent Tuberculosis Infection (LTBI): Isoniazid is commonly prescribed as a preventive measure for individuals with latent tuberculosis infection, especially those at high risk of developing active TB.
• Prophylaxis in Close Contacts: It might be given as a preventive measure to individuals who have been in close contact with someone diagnosed with active tuberculosis to reduce the risk of infection.
• Certain Atypical Mycobacterial Infections: Isoniazid may be used in combination with other antibiotics for the treatment of specific atypical mycobacterial infections.

What special precautions should I follow?

When taking isoniazid, individuals should be aware of and follow specific precautions to ensure the safe and effective use of the medication. Some important precautions include:

• Liver Function Monitoring: Regular monitoring of liver function is essential during isoniazid treatment. Liver toxicity is a potential side effect, and early detection is crucial to prevent severe complications.
• Avoid Alcohol: Alcohol consumption should be minimized or avoided during isoniazid treatment, as it can increase the risk of liver toxicity.
• Peripheral Neuropathy: Isoniazid can cause peripheral neuropathy (numbness, tingling, or pain in the hands or feet). To mitigate this risk, your healthcare provider may recommend vitamin B6 (pyridoxine) supplementation.
• Drug Interactions: Inform your healthcare provider about all the medications you are taking, as isoniazid can interact with other drugs. This includes over-the-counter medications, herbal supplements, and other prescription drugs.
• Pregnancy and Breastfeeding: Isoniazid is generally considered safe during pregnancy, but it’s important to discuss the potential risks and benefits with your healthcare provider. It is also excreted in breast milk, so the decision to breastfeed should be made in consultation with your healthcare provider.
• Pre-existing Liver Disease: Isoniazid should be used with caution in individuals with pre-existing liver disease.
• HIV Infection: Individuals with HIV infection may require adjusted dosages and monitoring during isoniazid treatment.

Always follow your healthcare provider’s advice and inform them of your complete medical history, including any pre-existing conditions and medications you are taking. If you experience any side effects or have concerns during treatment, contact your healthcare provider promptly. Never stop or adjust the dosage of isoniazid without consulting your healthcare provider, as it could affect the effectiveness of the treatment.

What special dietary instructions should I follow?

• Food interactions: Isoniazid should be taken on an empty stomach, at least one hour before or two hours after meals, unless otherwise directed by your healthcare provider.
• Tyramine-containing foods: While there are no specific dietary restrictions with isoniazid, it’s advisable to avoid foods high in tyramine (aged cheeses, cured meats, certain fermented foods) as interactions with isoniazid may cause an increase in blood pressure.
• Vitamin B6-rich foods: If your healthcare provider recommends vitamin B6 supplementation, consider incorporating foods rich in B6 into your diet, such as poultry, fish, potatoes, and fortified cereals.

What should I do if I forget a dose?

If you forget to take a dose of Isoniazid, follow these general guidelines:

• Take it as soon as you remember: If you miss a dose, take it as soon as you remember. However, if it’s almost time for your next scheduled dose, skip the missed one and continue with your regular dosing schedule.
• Don’t double up: Do not take a double dose to make up for a missed one. Taking extra medication may increase the risk of side effects.
• Inform your healthcare provider: If you frequently forget doses or have concerns about your medication schedule, talk to your healthcare provider. They can provide guidance and may adjust your treatment plan if necessary.

What side effects can this medication cause?

Isoniazid is an antibiotic commonly used in the treatment of tuberculosis (TB). While it is effective in treating TB, it can also have side effects. It’s important to note that not everyone will experience these side effects, and the severity can vary from person to person. Some common side effects of isoniazid include:

• Peripheral neuropathy: This is a common side effect, particularly with long-term use. It can cause numbness, tingling, or pain in the hands or feet. Taking vitamin B6 (pyridoxine) supplements can help prevent or alleviate this side effect.
• Liver toxicity: Isoniazid can cause liver damage in some individuals. Regular monitoring of liver function through blood tests is typically recommended during treatment.
• Gastrointestinal effects: Some people may experience nausea, vomiting, or abdominal pain.
• Rash: Skin reactions, such as a rash or itching, may occur.
• Fever: Isoniazid can cause an elevated body temperature in some cases.
• Joint pain: Some individuals may experience joint pain or stiffness.
• Optic neuritis: In rare cases, isoniazid has been associated with inflammation of the optic nerve, which can affect vision.

It’s important to report any unusual or severe side effects to your healthcare provider promptly. Additionally, it’s crucial to take isoniazid as prescribed and attend follow-up appointments to monitor for potential side effects. If you experience any signs of severe side effects, such as jaundice (yellowing of the skin or eyes), persistent nausea and vomiting, or signs of an allergic reaction (difficulty breathing, swelling of the face or throat), seek medical attention immediately.

This information is not exhaustive, and individual responses to medication can vary. Always consult with your healthcare provider for personalized advice and guidance based on your specific health condition.

What should I know about storage and disposal of this medication?

Storage and Disposal:

• Storage: Keep isoniazid in its original container, tightly closed, and at room temperature. Avoid exposure to excessive heat, moisture, and light. Follow any specific storage instructions provided by your pharmacist or healthcare provider.
• Disposal: Dispose of unused or expired medication in a safe and environmentally friendly way. Do not flush medications down the toilet unless instructed to do so. Ask your pharmacist about local guidelines for medication disposal.

In case of emergency/overdose

If you suspect an overdose or experience severe symptoms, seek emergency medical attention immediately. Overdose symptoms may include:

• Seizures
• Severe dizziness or lightheadedness
• Unsteadiness or difficulty walking
• Confusion
• Slurred speech

What other information should I know?

• Follow your healthcare provider’s instructions: Take isoniazid exactly as prescribed. Do not alter the dosage or stop taking the medication without consulting your healthcare provider.
• Regular monitoring: Your healthcare provider may order regular blood tests to monitor liver function and ensure the medication is not causing adverse effects.
• Complete the course: Finish the entire course of isoniazid as prescribed, even if you start feeling better before completing it. Skipping doses or stopping early may result in incomplete treatment and increase the risk of developing drug-resistant tuberculosis.
• Avoid alcohol and certain foods: Limit or avoid alcohol consumption while taking isoniazid, as it may increase the risk of liver problems. Be cautious with foods containing tyramine, as they may interact with isoniazid and cause an increase in blood pressure.
• Inform healthcare providers: Inform all healthcare providers involved in your care that you are taking isoniazid. This includes dentists, surgeons, and other specialists.
• Drug interactions: Inform your healthcare provider about all other medications, supplements, and herbal products you are taking to avoid potential drug interactions.
• Allergic reactions: If you develop signs of an allergic reaction, such as rash, itching, swelling, severe dizziness, or difficulty breathing, seek medical attention promptly.

Always consult your healthcare provider or pharmacist if you have specific questions or concerns about your medication. They can provide personalized guidance based on your health status and medical history.