Guanidine (Oral)

As a drug that works within the nervous system, Guanidine is useful in helping to restore strength in patients suffering from Eaton-Lamberts syndrome.


The drug Guanidine is taken by patients who suffer from Eaton-Lamberts syndrome. It is used to help treat the muscle tiredness and weakness associated with this condition. Eaton-Lamberts syndrome, an autoimmune disorder, affects a patient's nervous system, so Guanidine works by helping the nervous system to restore its strength.

Do be aware that you can only obtain Guanidine following a doctor's prescription. It is not suitable for all sufferers of Eaton-Lamberts syndrome, as it is known to interact with a variety of different drugs and can potentially cause some very unwanted side effects.

Conditions Treated

  • Eaton-Lamberts syndrome

Type Of Medicine

  • Tablet

Side Effects

As well as helping to treat this unwanted muscle weakness, it is possible that Guanidine will cause you to experience certain side effects. In some cases, these side effects should give you little cause for concern, but, in other cases, they will require attention. Directly below is a list of the more serious possible side effects. If you experience any of the effects listed below, you should contact your doctor immediately.

Incidence not known

  • Loss of appetite

As well as these more serious effects, it is possible that you will experience less serious ones, which give less cause for concern. In fact, you may find that such side effects will pass over time, as your body adjusts to this new medicine. Directly below is a list of such side effects. Do be aware that, if you experience any of the following and they are bothering you or lingering, you can still contact your doctor, as they may be able to advise ways to reduce the effects. Alternatively, they may adjust your dosages.

Incidence not known

  • Quick to react or overreact emotionally

Though the above lists are fairly extensive, they are not necessarily all-inclusive. This means it is possible that you will still experience other side effects. If this is the case and if the side effects are worrying you, then you should contact your doctor for guidance.


Below you can find the typical dosages that are prescribed to patients suffering from Eaton-Lamberts syndrome. Do be aware that the doses given to you will not necessarily be the same as those below. This is because each patient is prescribed on a personal basis and exact doses are calculated to suit their exact medical needs. You should stick to your doctor's prescription and never take Guanidine any more frequently, or take any more of it, than you are told to do by your doctor.

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    • Adults: The exact dosage is based on your bodyweight. Usually, the starting dose will be 10 to 15 mg per kg of body weight, taken each day in three or four doses. Then, your doctor will adjust the dosage as necessary. The total daily dosage is never usually more than 35 mg per kg per day.
    • Children: The exact doses and use will need to be determined by your doctor.

It is important that you do not miss any doses, as this will impact upon the effectiveness of the treatment. However, if you have missed a dose for whatever reason, then you should take it as soon as possible. The only exception is if it is almost time for you to take your next dose - simply skip the missed one. It is important that you never double dose.

You should follow your doctor's prescription as closely as possible and never take this medicine for longer than is needed. If you do have any questions about your dosage, you should address these with your doctor before making any changes.


It is possible that Guanidine will interact with other drugs you are currently taking. In many cases, these interactions will usually be avoided. However, under certain circumstances, they may be necessary.

Either way, you should be clear and honest in informing your doctor of all drugs you currently take. This includes both prescription and non-prescription drugs. If a known interaction will occur, your doctor may decide that Guanidine is not a suitable medicine, and advise something different. Alternatively, if it is necessary for you to take both, then they will likely alter one or both of the doses you are given. Directly below is a list of drugs with which it is usually not recommended you take Guanidine:

  • Donepezil

As well as interacting with drugs, it is possible that Guanidine will interact with certain aspects of your dietary intake. Your doctor may, therefore, wish to make adjustments to what you eat, drink, or smoke. You should inform your doctor of what you typically consume, and then follow any dietary guidance they give you. For example, it may be necessary for you to consume less tobacco or alcohol.

Finally, Guanidine could potentially interact with other medical conditions you have or have had. You should give your doctor a rundown of all present and previous medical problems you have had. In particular, take care in highlighting any of the following:

  • Thrombocytopenia (low platelets in the blood) you should use this drug with caution as it may make this condition worse


Before being able to prescribe you this medicine, your doctor will need to decide whether or not it is indeed the best course of treatment for you. They will need to examine you and understand the extent of your condition. As a part of this examination, they will need to be made aware of any and all allergies you have. This includes any allergies to preservatives, dyes, foods or animals.

As of writing, safety and efficacy have not been established for younger patients using this medicine, because no suitable studies have been performed on pediatric patients taking this medicine. Your doctor will be best placed to advise you of any increased risks to your child when taking this drug. Together, you can then weigh any risks against the benefits.

No information is available on the relationship between Guanidine and geriatric patients. This could be because suitable studies have not yet been performed. Your doctor can advise whether or not you are at any increased risk of using this medicine.

As of writing, there are no adequate studies that have been performed on breastfeeding women using Guanidine. Again, your doctor will be best placed to advise of any risks and to weigh them against the benefits of using this drug.

Whilst taking this medicine, your doctor will want to have regular appointments with you to see how your condition is progressing. It is important that you attend all such appointments. They are a chance for your doctor to make any necessary adjustments to your prescription, which are in your best interests. It may be necessary to have urine or blood tests during these appointments.

Taking Guanidine may cause the number of certain types of blood cells in your body to become lower. As such, you may be at greater risk of getting infections. To help avoid this happening, follow these steps:

  • Remember to wash your hands often

Unless first approved by your doctor, do not take any other medicines at the same time as Guanidine. This includes all prescription and non-prescription drugs, as well as any vitamin or herbal supplements.


You should store this medicine in a sealed container and keep it at room temperature. It should not be allowed to freeze and should be kept away from direct light, heat and moisture. It can be potentially dangerous for children, so keep it stored somewhere safe.

Once you are finished with a course of treatment, you should dispose of any remaining medication in a safe and sensible manner, as advised by your doctor. Similarly, if you have any medicine that goes out of date, you should dispose of this in the same way.


If you suffer from Eaton-Lamberts syndrome, then Guanidine can potentially be a very helpful drug in relieving the weakness and tiredness in your muscles. However, it is not necessarily suitable for all patients, as it can interact with certain drugs and other medical conditions. This is why you should be open and honest with your doctor about the extent of your condition.

Your doctor may issue you with other lifestyle or dietary changes that you should make whilst using this medicine. You should follow these guidelines as closely as possible. Above, you can find full details on side effects that you may experience whilst using this drug. If you have any of the more serious ones, then you should contact your doctor immediately for advice. If you have any other questions about this drug, or how it is affecting you, then you should address these questions with your doctor, as well.