Topamax

Drug Name - Topamax (Topiramate)

Topamax (Topiramate) is an orally administered drug used in the prevention of epileptic seizures.

Indications for Use

Seizures are categorized as partial or generalized depending on the extent of involvement of the brain. Topamax is collectively used with other drugs which prevent seizures both in adults as well as children between the age group of 2-16 years who are suffering from partial or generalized seizures of tonic-clonic type (extended duration of contractions of body muscles leading to rigidity and jerking).

Capsules of Topamax sprinkle have been approved for use in patients aged 10 or more. Topamax is approved for use in children in the age group of 2 and more and suffering from Lennox-Gastaut Syndrome that amounts to around 10 percent of child epilepsy cases and is a very severe type of the condition. The syndrome might cause many problems in the child including reduction in the overall development and several seizures of mixed type in a day. The many type of epileptic seizures encountered in this syndrome are atonic (falling due to decrease in muscle tone and alertness); tonic (rigidity of the body, rolling of the eyes, dilated pupils and breathing becoming shallow and irregular); myoclonic (abrupt and sudden jerking); and absence (incidents of blank staring).

Instructions for Use

Topamax is usually begun by providing it in low strengths of 25 to 50 mg in a day and then gradually increased as per the instructions provided by about 25 to 50 mg every week till the required strength is arrived at. This gradual increase in dosage decreases the possibility of side effects. However, in children the beginning dose is a maximum of 25 mg in a day (1-3 mg/kg/day).

The optimum dosage in adults is 200 mg taken twice in a day although many patients enjoy reduction of symptoms by just taking 200 mg/day. However, some patients might require more than 200mg/day. The optimum dose in children is 2.5-4.5 mg/kg/two times a day. Those taking topamax should have good consumption of water to prevent the formation of stones in the kidney.

Drug Category and Mechanism of Action

Topamax is an orally administered drug used in the treatment of epileptic seizures. It is prescribed to patients who have not found results from the intake of other anti-epileptic medication and is about 25 percent of the entire cases of people suffering from epilepsy. Topamax also helps in people suffering from migraine headache.

The epileptic seizures occur as a result of abnormal nerve activity within the brain that spreads over a portion of the brain or may be more generalized. Although it is not clear as to how exactly topamax helps in reducing the epileptic seizures, it is believed that it has an effect in altering the actions or production of neurotransmitters inside the brain thereby helping in reducing the abnormal nerve activity inside the brain. This helps in preventing the transmission of impulses to other nerve cells within the brain thereby reducing the seizures. Another line of thought is that they do not have any action on the neurotransmitters but have a direct action on the nerve itself.

If You Miss a Dose

In case you forget to take a dose, consume it as once you recollect that you missed a dose. In case the time when you remember is close to the next scheduled dose, avoid taking the dose you have missed and take the tablet only at the next scheduled time.

Storing Instructions

Topamax tablets are best stored at room temperature between 15-30 degrees C (59-86 degrees F). The sprinkle capsules are best stored below 25 degrees C (77 degrees F).

Safety Information

Some medications like acetazolamide (Diamox), carbamazepine (Tegretol), dorzolamide (Trusopt), dichlorphenamide (Daranide), methazolamide (Neptazane) and phenytoin (Dilantin) have an action of escalating the excretion of topamax from the body which necessitates a higher dosage of the latter to have optimum actions. These medications also increase the chances of formation of kidney stones when they are combined with topamax.

Topamax has the effect of decreasing estrogen levels in women on oral contraceptives thereby causing reduction of the effectiveness of the latter and increasing the possibilities of unwanted pregnancy.

Patients taking topamax or a combination of antiepileptic drugs including topamax have higher chances of developing nerve toxicity if they are on some gingko supplements. This nerve toxicity is a result of a chemical known as 4'-O-methylpyridoxine which is a contaminant in these supplements.

Avoid intake of this medication if you have experienced any kind of allergy to the drug or any of the ingredients in the drug. But, if you are deciding to stop the medication please check with the doctor before you do so. It is essential to remember that symptoms of the condition might become worse if the drug intake is suddenly ceased. You might be advised some lab tests to test the level of bicarbonate in the blood before beginning the medicine and to monitor for side effects during the treatment.

It is important to mention the intake of this drug if you are going in for any other medical or dental treatment. Alcohol and depressant drugs will have increased effect when you are on this medication. It is essential to avoid driving or other activities that pose a risk to you and others until you are sure of the effects of the medication on these activities. But, when the drug is combined with other medications or with alcohol it reduces your capacity to perform these activities safely.

The medicine has a tendency to decrease sweating which might pose dangerous effects on the body temperature. This tendency is higher in children and is more during hot seasons and while performing strenuous activities. So, it is essential to consume more amount of water and to wear thin clothes during hot weather and during exercise or strenuous activities. Monitor yourself for any possibilities of reduction in sweating. If you are experiencing this, then move over to a cooler area and/or cease the strenuous activity at the earliest. See a doctor immediately if the temperature of the body goes beyond normal or if you experience any mood swings, dizziness or headache.

If you are prescribed any new medication, bring the intake of topamax to the physician or the pharmacist immediately to know whether there will be any interaction and possibility of adverse effects. Women on this medication should remember that the actions of oral contraceptives are far reduced due to the actions of the drug. So, it might become essential to use some other form of birth control when you are on the medication.

Discuss with your physician or the pharmacist on any doubts you have regarding the intake of this medication. Women who are on the drug who plan to get pregnant must seek advice from the doctor to know the possibilities of any risks on the developing fetus from the drug. Currently, it has not been studied whether the medication passes through the breast milk. So, if you are nursing your child and are on the medication, it is best to seek advice from the physician or pharmacist to know about possible risks to the baby.

Probable Adverse Effects

The commonly observed adverse effects in adults include dizziness, difficulties with remembering, problems with vision, coordination and speech along with sensory distortion. The commonly observed adverse effects in children include drowsiness, reduced appetite and weight, concentration problems, aggression, tiredness, memory problems and nervousness.

23 cases of patients developing sudden eye or vision problems have been reported from the day the drug received approval till 8-17-01. The onset of symptoms was in the very first month of therapy and included the sudden development of pain in the eye and/or reduction in vision. On examination of the eyes, it showed redness, reduction of depth in the anterior chamber, myopia, increase in ocular pressure with or without the presence of dilatation of the pupils. Due to the increase in fluids in the eye, the lens and the iris of the eye might get shifted more anteriorly leading to secondary angle closure glaucoma. If such a problem occurs, patients are advised to cease topamax immediately after consulting the physician.

Additional Information

It is essential to perform lab and medical tests (like eye examination) to check for side effects and the effects of the drug at prescribed intervals during the therapy. This medication should not be shared with others and should not be used for any other conditions apart from what it has been prescribed for. Do not place the medicine where it can be reached by children or pets. If you have been prescribed the drug for a longer duration, it is essential to get additional supplies of the drug before the existing prescription is finished.