It's exceptional to get relief at your present dose. Here is a widely used protocol for it's use. Might print it for your doc.

Re. stopping. No clinical test; many folks come off about 2-4 weeks after their last attack. Start again if you start getting attacks.
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Headache. 2004 Nov;44(10):1013-8.   

Individualizing treatment with verapamil for cluster headache patients.

Blau JN, Engel HO.


    Background.-Verapamil is currently the best available prophylactic drug for patients experiencing cluster headaches (CHs). Published papers usually state 240 to 480 mg taken in three divided doses give good results, ranging from 50% to 80%; others mention higher doses-720, even 1200 mg per day. In clinical practice we found we needed to adapt dosage to individual's time of attacks, in particular giving higher doses before going to bed to suppress severe nocturnal episodes. A few only required 120 mg daily. We therefore evolved a scheme for steady and progressive drug increase until satisfactory control had been achieved. Objective.-To find the minimum dose of verapamil required to prevent episodic and chronic cluster headaches by supervising each individual and adjusting the dosage accordingly. Methods.-Consecutive patients with episodic or chronic CH (satisfying International Headache Society (IHS) criteria) were started on verapamil 40 mg in the morning, 80 mg early afternoon, and 80 mg before going to bed. Patients kept a diary of all attacks, recording times of onset, duration, and severity. They were advised, verbally and in writing, to add 40 mg verapamil on alternate days, depending on their attack timing: with nocturnal episodes the first increase was the evening dose and next the afternoon one; when attacks occurred on or soon after waking, we advised setting an alarm clock 2 hours before the usual waking time and then taking the medication. Patients were followed-up at weekly intervals until attacks were controlled. They were also reviewed when a cluster period had ended, and advised to continue on the same dose for a further 2 weeks before starting systematic reduction. Chronic cluster patients were reviewed as often as necessary. Results.-Seventy consecutive patients, 52 with episodic CH during cluster periods and 18 with chronic CH, were all treated with verapamil as above. Complete relief from headaches was obtained in 49 (94%) of 52 with episodic, and 10 (55%) of 18 with chronic CH; the majority needed 200 to 480 mg, but 9 in the episodic, and 3 in the chronic group, needed 520 to 960 mg for control. Ten, 2 in the episodic and 8 in the chronic group, with incomplete relief, required additional therapy-lithium, sumatriptan, or sodium valproate. One patient withdrew because verapamil made her too tired, another developed Stevens-Johnson syndrome, and the drug was withdrawn. Conclusions.-Providing the dosage for each individual is adequate, preventing CH with verapamil is highly effective, taken three (occasionally with higher doses, four) times a day. In the majority (94%) with episodic CH steady dose increase under supervision, totally suppressed attacks. However in the chronic variety only 55% were completely relieved, 69% men, but only 20% women. In both groups, for those with partial attack suppression, additional prophylactic drugs or acute treatment was necessary. (Headache 2004;44:1013-1018).

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SLOW-RELEASE VERAPAMIL

Dr. Sheftell applauded the protocol for verapamil used by Dr. Goadsby and colleagues, which entailed use of short-acting verapamil in increments of 80 mg. “This method was suggested by Lee Kudrow, MD, 20 years ago as an alternative to slow-release verapamil,” Dr. Sheftell noted.

“I would agree with using short-acting verapamil, rather than the sustained-release formulation, in cluster headache,” he said. “I prefer the short-acting formulation with regard to ability to titrate more accurately and safely. My clinical experience anecdotally demonstrates improved responses when patients are switched from sustained-release verapamil to short-acting verapamil.”

Dr. Goadsby agreed that his clinical experience was similar. “There are no well-controlled, placebo-controlled, dose-ranging studies to direct treatment. This is one of those areas where clinicians who treat cluster headache have to combine what modicum of evidence is available with their own clinical experience,” Dr. Sheftell commented.

I go with 720 per day. I stop when Ive gotten two weeks pain free.

Routinely at 720mg Verapamil  CR combined with 1200mg Lithium Carbonate daily for about the last decade.   

My Neurologist recently suggested increasing the dosage of Verapamil to 960mg in an attempt to address increased CH activity.  With the increased Verapamil I’m currently at the lowest levels of CH activity that I’ve experienced in years.

My results after increasing Verapamil to 960mg on August 14th.

July - 2,451 minutes / average severity 2.72 (out of 5)
Aug - 1,484 minutes / averaging 2.32
Sept.    483 minutes / averaging 1.96
Oct.        41 minutes / averaging 1.25

In the past we’ve adjusted Verapamil down in when/if CH activity decreased.  Given the results so far I’m not sure how we’ll handle things this time.  It’s something I’ll have to work out with the Doc.

Keep in min that it’s not a perfect solution, in my case CH activity will ramp up again in late fall and traditionally peak in May or June no matter what I'm on.  I’m just hoping this Verapamil increase helps keep things are a little more under control this year.   

Routine EKG’s should be done prior to your Doctor visits.  Studies indicate that using high doses of Verapamil to treat headaches can result in heart problems that are usually reversible by discontinuing the drug.



burnt-toast
(Tom)    

I was getting 2 CH per day and used cafergot to ease pain when required. Eventually I tried taking 2 cafergot per day and it worked. CH ceased but then the doc told me I could not continue with cafergot. He prescribed verapamil but i never took it. CH have not come bac for a month so do you think the cafergot cured it?

Graemel wrote on Nov 2^nd, 2010 at 7:28am:


Ergotamine and caffeine in combination (cafergot, or formerly ercaf) is an old line intervention. Still around, though, and can work. Ergotamine is a poison in high doses and comes from mold...sailing men of old, eating moldy bread I think, began to see "St Elmo's Fire," a greenish tinge to the outline of hard lines. It can also cause limb numbness and tingling. Like anything else it needs to be monitored. It's also addicting as hell. I had a hard time getting of it. Hope this helps. God bless! lance

I used Verapamil successfully for three cycles.
400mg / day of the regular release formulation following the guidelines posted by Bob above.

Before that I tried using the sustained release formulation without much luck.

As soon as my cycle was over I'd come off it as quickly as possible.

-Dennis-

I am on 920mg of verap a day 1/2 morning 1/2 at night with 200mg
topomax most of it at night.  Take about 2 5hr energy drinks
and 5000iu of D plus some other vitties!     Will take it till no more hit for awhile. month or 2.