Question: I have MS and have been taking LDN for several years. About 6 weeks ago I started taking 4AP (4-Aminopyridine).

I weigh 100lb (+ or -), so my optimum dose is 23mg/day. I haven’t been able to get up to that dose, mostly because I’m not sure how to fit 4 or 5 doses into my day (I have 5mg caps).

Given my weight, should I be taking 20mg or 25mg? If I only have time in my day for 3 doses, should I double up on some? If my last dose would be at 8 or 9 pm and I’m just sitting around at home and going to bed in a couple of hours, should I take it anyway?

Larry’s Response: Side effects are common and usually mild when starting 4AP. They soon disappear. That’s why we strongly recommend using it according to a dosing schedule – and ramping up to the appropriate dose. There are dosing guidelines, but the appropriate dose is highly individual. It is important to start the ramping process over if you stop using the medicine completely for a few days.

4AP has a relatively short life in the body. It is dosed frequently (3 to 5 times a day) in order to establish and maintain an effective blood level. Common times are breakfast, lunch, dinner and early evening, depending on the planned activity for the evening. If you’re just going to sit around and then go off to bed, I wouldn’t think you would need a dose. Individualize the amount used and the times to coincide with your activity. You may want to use 5mg at breakfast, then another 5 at 10 am, then 5 at lunch, mid-afternoon, and after supper. The total daily amount is a guide, not set in stone. However, taking excessive amounts can cause a problem. It isn’t fatal, but the side effects are unpleasant. Doubling a dose during the day (10mg) is far less of a problem than taking extra just to catch up. I prefer adding another dosing time, again depending on the activity planned.

Think of this medicine along the same lines as, say, drinking water. People generally drink when they are thirsty, not because they have it on a schedule. Most medicines should be taken according to somewhat strict schedules. 4AP isn’t that serious – as long as you don’t swallow a whole day’s worth at bedtime just because you forgot the doses during the day.

Your said dose is around 20mg to 25mg per day. There isn’t a precise amount – just as there isn’t a consistent time frame we call a day. I’d suggest ignoring the word, optimum. Some days start early and end near midnight. Others start at 10 am and come to an end with a cup of tea, a good book, and bed by 9 pm. Your task is to evaluate your day and include 4AP at reasonable intervals. Some days you may take 20mg (4 capsules) and others may be 25mg (5 capsules). There may also be times when you only take two or three doses.

4AP dosing is flexible and the dosing is governed by the user. 4AP does not accumulate in the body, so you are essentially starting over every morning.

For more information on 4-Aminopyridine (often referred to as DALFAMPRIDINE) click here.