CME INDIA Case Presentation by Dr N. K. Singh, Dhanbad.
CME INDIA Case Study
CASE: This young man develops moderate headache only triggered by smell of smoke, chewing tobacco, incense scent or similar pungent smell.
Frequency… Only after exposure of smell.
Duration – 2 yrs.
History: Had some stress anxiety disorder 4 yrs. back, took estalopam for 3 months.
What is the diagnosis??
CME INDIA Discussion:
Dr Rashmi Sinha, Ranchi: Migraine.
Dr Bhanu Pratap Singh, Siwan, Bihar: His headache is precipitated by fragrance, of different types. Plz look the way he is pointing to his head-unilateral. So, migraine should be kept in d/d. Also, leads to vomiting.
Dr Abhishek, DM, Neuro, Patna: This is migraine, precipitated by smell. Very common scenario ….
Dr Ujjawal Roy, DM, Neuro, Ranchi: Yes, its migraine.
Dr Anupum Gupta, Asansol: Never heard, read about such manifestation. What’s the diagnosis? Also, enlighten about the cause of body reacting to such a trigger.
Dr Anu Jain Ambala, Cant.: Migraine may be the cause.
Dr Anant Sheel Chaudhary, MD Pulmonary medicine, Lucknow: Migraine triggered by these.
Dr Anupum Gupta, Asansol: Maybe but why such bizarre bodily reaction every time?
Dr Ranjan Kumar MD, Patna: It’s typical feature of migraine, I too have come across patients complaining of particular smell induced headache responding well to Vasograin or Zolmist Sprays. Probably olfactory nerve endings travels toward limbic systems and this system plays important role in migraine.
Dr Vivek Gupta, Surat: Diagnosis migraine.
Dr N. K. Singh: What is the drug of choice in this case?
Dr Abhishek, DM, Neuro, Patna: Treatment is same sir. For male Tryptomer or divalproate … Another option Tooiramate: Beta blocker we generally avoid due to side effect.. Flunatazine is the another one.
Dr Anil Kumar Pshy, Ranchi: What about dilantin?
Dr Abhishek Kr Singh, DM, Neuro, Patna: We never used it. AED has no role in migraine but it’s useful in central autonomic disturbances associated with migraine. Phenytoin in osmophobia. There are few papers on it but I never used it sir…!
Dr Ashok Kumar, DM, Neuro, Ranchi: This of smell as a trigger for migraine is known. But we rarely pay much attention to it. I tried to find some references. Osmophobia is abnormal heightened sensitivity to smell. It can be present in other conditions also — pregnancy (contributing to hyperemesis?), hepatitis, psychosis etc. But it is also associated with migraine.
The following points are notable:
1. Osmophobia may persist between migraine episodes in some patients. One study claimed it presence in almost 40% patients – both with or without aura (Zanchini et all 2007).
2. Osmophobia is not a defining symptom but it may be more specific for migraine. It may differentiate migraine from Tension-type Headache.
3. Osmophobia is a frequent Premonitory symptom. It may be present in majority of patients. One has to ask for it specifically. The patient may wrongfully MISTAKE this Osmophobia as migraine trigger. Therefore, the sequence of events may be — Premonitory symptoms including Osmophobia, Aura (may or may not) followed by headache.
Among Osmophobic patients with migraine, smell may trigger headache in 25%. BUT, as explained, that sensitivity to smell may be part of migraine symptomatology. It may be the effect Not the cause.
In this patient, also osmophobia as a Premonitory symptom should be ruled out.
Treatment should be same as that of migraine. There are conflicting claims about the effect on Osmophobia.
CME INDIA Learning Points:
- Osmophobia is defined as intolerance to odors and it is associated to primary headaches, particularly to migraine with or without aura. It occurs during headache attacks and/or in the period between headache attacks. It is not yet known specific treatment for osmophobia.
- From experience in one case, phenytoin should be considered as possible prophylactic treatment for osmophobia between headache attacks in migraine patients. Migraine prophylaxis provided a marked improvement in the frequency and intensity of headache attacksof this patient, but osmophobia remained unchanged. A prophylactic treatment with phenytoin was started, at a dose of 100 mg once a day. After 90 days, the patient became asymptomatic and remained without osmophobia for the following two years
(Silva-Néto RP (2016) Phenytoin in the Treatment of Osmophobia in Migraine Patient: A Case Report. J Clin Case Rep 6: 749. doi:10.4172/21657920.1000749)
- The exact mechanism of osmophobia is unknown. However, a study by fMRI during headache attacks in migraine patients and normal subjects showed increased activity of the limbic system and brainstem in response to olfactory stimulation, and only in migraine patients. These findings have demonstrated that olfactory processing is altered during headache attacks in migraine patients, suggesting that there are specific neuronal connections between the olfactory and trigeminal nociceptive systems.
- Osmophobia interferes in the quality of life of migraine patients, as some patients are daily exposed to odors in their professional activities. In addition, osmophobia is a critical factor for suicidality in migraine patients. For those reasons, it becomes necessary to treat osmophobia.
- Several categories of drugs are used in migraine prophylaxis, such as beta-adrenergic blockers, tricyclic antidepressants, calcium channel blockers, serotonergic antagonist, antiepileptics, and others. All of these drugs are effective in controlling pain, but with no influence in osmophobia.
- Cognitive-behavioral therapy is a suggestion of non-drug therapy for osmophobia. It is based in the exposure of the patient to odor and thus helps educate him/her about his/her odor intolerance. Hypnotherapy and relaxation techniques are other alternative therapies in the control of osmophobia
Based on links shared by Dr Anil Kumar [http://www.jscholaronline.org/full-text/JNND/5_101/Migraine-and-osmophobia.php ; https://pubmed.ncbi.nlm.nih.gov/23832131/]
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Amazing effort by you sir..kudos
Good discussion.
Very good case history and most of us will benefited by such example and explanations.
Thank you Sir.