WARNING

Isoniazid is a medication primarily used to treat tuberculosis (TB). While it is effective in treating TB, it also carries some risks:

• Liver Damage: One of the most significant risks associated with isoniazid is liver damage, particularly in people with pre-existing liver conditions or those who consume alcohol regularly.
• Peripheral Neuropathy: Isoniazid can cause damage to the nerves, leading to symptoms such as tingling, numbness, and weakness in the hands and feet.
• Drug Interactions: Isoniazid can interact with other medications, potentially leading to adverse effects or reducing the effectiveness of other drugs.
• Allergic Reactions: Some individuals may experience allergic reactions to isoniazid, which can range from mild skin rashes to severe anaphylaxis.
• Psychiatric Effects: In rare cases, isoniazid has been associated with psychiatric side effects such as depression, hallucinations, and psychosis.
• Vitamin B6 Deficiency: Long-term use of isoniazid can lead to a deficiency in vitamin B6 (pyridoxine), which is necessary for various bodily functions.

It’s essential for individuals taking isoniazid to be closely monitored by a healthcare professional to minimize these risks and ensure the medication’s effectiveness in treating tuberculosis.

Why is this medication prescribed?

Isoniazid is prescribed primarily for the treatment of tuberculosis (TB). It is often used in combination with other medications as part of a multi-drug regimen to effectively treat TB infections.

How should this medicine be used?

Here’s how isoniazid is typically used:

• Dosage: The dosage of isoniazid can vary depending on factors such as the patient’s age, weight, and the severity of the TB infection. It is usually taken once daily, but sometimes it may be prescribed multiple times per day.
• Duration:Treatment with isoniazid for TB typically lasts for several months, often ranging from 6 to 9 months or longer. It’s crucial to complete the full course of treatment as prescribed by your healthcare provider, even if symptoms improve before the medication is finished.
• Administration: Isoniazid comes as a tablet and a solution (liquid) to take by mouth without food. However, it’s essential to follow your healthcare provider’s instructions regarding when and how to take the medication.
• Monitoring: While taking isoniazid, your healthcare provider will likely monitor you closely for any signs of side effects or complications, such as liver function tests to check for liver damage.
• Combination Therapy: Isoniazid is often prescribed in combination with other medications, such as rifampin, pyrazinamide, and ethambutol, to prevent the development of drug-resistant strains of TB and to improve treatment efficacy.
• Preventive Therapy: In addition to treating active TB infections, isoniazid may also be prescribed for preventive therapy in individuals who have been exposed to TB but have not yet developed active disease. This is known as latent TB infection treatment and is aimed at reducing the risk of developing active TB in the future.

It’s crucial to take isoniazid exactly as prescribed by your healthcare provider and to communicate any concerns or side effects you experience during treatment.

Other uses for this medicine

Other than its primary use in TB treatment, isoniazid can also be used as a preventive measure in individuals who have been exposed to TB but have not developed an active infection. This is often referred to as “latent TB infection” treatment.

What special precautions should I follow?

Regarding special precautions to follow when taking isoniazid:

• Liver Function Monitoring: Regular monitoring of liver function is essential during treatment with isoniazid, as the medication can cause liver damage. Liver function tests should be performed before starting treatment and periodically throughout the course of therapy.
• Avoid Alcohol: Individuals taking isoniazid should avoid consuming alcohol, as it can increase the risk of liver damage.
• Vitamin B6 Supplementation: Long-term use of isoniazid can lead to vitamin B6 deficiency. In some cases, healthcare providers may recommend supplementation with vitamin B6 (pyridoxine) to prevent or alleviate symptoms of deficiency, such as peripheral neuropathy.
• Drug Interactions: Inform your healthcare provider about all medications, supplements, and herbal products you are taking before starting isoniazid, as it can interact with certain drugs, including anticonvulsants, antiretrovirals, and some psychiatric medications.
• Peripheral Neuropathy: Be aware of symptoms of peripheral neuropathy, such as tingling, numbness, or weakness in the hands and feet, and report any such symptoms to your healthcare provider promptly.
• Pregnancy and Breastfeeding: If you are pregnant, planning to become pregnant, or breastfeeding, discuss the risks and benefits of isoniazid with your healthcare provider. Isoniazid may be used during pregnancy if the benefits outweigh the risks, but close monitoring is necessary. It is also excreted in breast milk, so caution is advised while breastfeeding.

Always follow your healthcare provider’s instructions and recommendations when taking isoniazid to ensure safe and effective treatment.

What special dietary instructions should I follow?

There are no specific dietary restrictions associated with isoniazid. However, it’s generally recommended to take isoniazid with or without food, as directed by your healthcare provider. Some individuals may experience gastrointestinal discomfort when taking isoniazid on an empty stomach, so taking it with food may help alleviate this.

What should I do if I forget a dose?

If you miss a dose of isoniazid, take it as soon as you remember. However, if it is almost time for your next dose, skip the missed dose and continue with your regular dosing schedule. Do not double the dose to catch up. It’s important to maintain a consistent dosing schedule to ensure the effectiveness of the medication in treating tuberculosis. If you have any concerns or questions about missed doses, consult your healthcare provider or pharmacist for guidance.

What side effects can this medication cause?

Isoniazid, like any medication, can cause side effects. Common side effects of isoniazid include:

• Nausea and vomiting: Many people experience nausea and vomiting when taking isoniazid, especially if taken on an empty stomach.
• Peripheral neuropathy: This is a condition that affects the nerves in the extremities, leading to symptoms such as tingling, numbness, or weakness in the hands and feet. This side effect is more common with long-term use of isoniazid and may be alleviated with vitamin B6 supplementation.
• Liver toxicity: Isoniazid can cause liver damage in some people, leading to symptoms such as abdominal pain, jaundice (yellowing of the skin or eyes), dark urine, and fatigue. Liver function should be monitored regularly during treatment with isoniazid.
• Allergic reactions: Some individuals may experience allergic reactions to isoniazid, which can range from mild skin rashes to severe reactions such as swelling of the face, throat, or tongue, difficulty breathing, or anaphylaxis.
• Psychiatric effects: In rare cases, isoniazid has been associated with psychiatric side effects such as depression, anxiety, hallucinations, and psychosis.
• Blood disorders: Isoniazid can affect the production of blood cells in some people, leading to conditions such as anemia (low red blood cell count) or thrombocytopenia (low platelet count).
• Other side effects: Other less common side effects of isoniazid may include dizziness, headache, joint pain, fever, and changes in vision.

It’s important to discuss any concerns or side effects you experience with your healthcare provider. They can provide guidance on managing side effects and may adjust your treatment regimen if necessary.

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

Storage of Isoniazid:

• Store isoniazid tablets or capsules at room temperature away from moisture, heat, and light.
• Keep the medication in its original packaging or container, tightly closed, and out of reach of children and pets.
• Do not store isoniazid in the bathroom or near the kitchen sink where it can be exposed to moisture.
• Follow any specific storage instructions provided by your pharmacist or healthcare provider.

Disposal of Isoniazid:

• Dispose of any unused or expired isoniazid medication properly to prevent accidental ingestion or misuse.
• Do not flush medications down the toilet or pour them down the drain unless instructed to do so.
• Consult your pharmacist or local waste disposal facility for guidance on the proper disposal of medication.
• You may also inquire about drug take-back programs in your community for safe disposal of unused medications.

In case of emergency/overdose

• If you suspect an overdose of isoniazid or experience severe symptoms such as seizures, difficulty breathing, loss of consciousness, or severe dizziness, seek immediate medical attention by calling emergency services (e.g., 911 in the United States) or visiting the nearest emergency room.
• Be prepared to provide information about the amount of isoniazid ingested, when it was taken, and any other medications or substances involved.

What other information should I know?

• Inform all healthcare providers involved in your care that you are taking isoniazid, including dentists, pharmacists, and specialists.
• Attend all scheduled appointments with your healthcare provider for monitoring of your condition and response to treatment.
• Avoid consuming alcohol while taking isoniazid, as it can increase the risk of liver damage.
• Notify your healthcare provider if you experience any new or worsening symptoms while taking isoniazid, including nausea, vomiting, jaundice, numbness or tingling, or changes in mood or behavior.
• Follow your healthcare provider’s instructions closely, including the recommended dosage and duration of treatment, to ensure the effectiveness of isoniazid therapy.

By following these guidelines, you can safely store, dispose of, and respond to emergencies related to isoniazid use.