Journal of Headache & Pain Management

Keywords

Alopecia; Dizziness; Headache; Minoxidil; Vertigo; Vasodilation

What is Known-What is New

Topical application of minoxidil can boost hair growth in female baldness. As this substance is a vasodilator which is absorbed and activated in the scalp it may lead to local vasodilation with headache and dizziness. It is available as over-the counter selfmedication. It is sometimes used as a ‘lifestyle’ substance for boosting hair growth by adolescents. Careful history taking is essential to identify this substance and should be considered in patients with unexplained headache and dizziness. Simple discontinuation will resolve the symptoms.

Introduction

Topical minoxidil treatment for the therapy of baldness and hair loss both in men and women is well known and reasonably safe. It is available as over-the counter self-medication and is sometimes used for ‘lifestyle’ purposes by adolescents who want to boost their hair growth. Side effects are often of dermatologic nature (pruritus, dermatitis, scaling), headache is observed in 4% of treated patients, dizziness/lightheadedness is a less common side effect [1] while systemic adverse events are rare [2].

Patient’s Medical Report

We report a 17-year old girl who presented with a sudden onset of severe headache and dizziness 2.5 weeks before admission, no nausea or vomiting was reported. The pain was unilateral on her right side, especially in the temporo-occipital region and radiated to her neck. Neither a circadian rhythm nor photophobia was described. There was no variation in pain intensity, however the pain worsened and became throbbing in the upright position which forced her to stay in bed for several days. She took normal food and drank 2-3 liters of fluid daily. For symptomatic treatment of headache paracetamol, acetylsalicylic acid and ibuprofen were administered. Apart from oral contraception for 2 years no longterm medication was initially reported. During her hospital stay she informed us of topical use of Regaine (2% minoxidil) on her entire scalp for a period of approximately 2.5 months because of presumed hair loss. She bought this compound as over-thecounter self-medication for ‘lifestyle’ purposes to boost hair growth. Hair loss was never verified by a medical professional.

Family history was unrevealing, only a mother’s aunt is known to suffer from migraine.

The physical examination of the adolescent was unrevealing, no arterial hypo-/hypertension was found however she was not able to stand upright due to pain and dizziness thus postural hypotension could not be excluded. Clinical neurological examination was unrevealing, especially the function of cranial nerves and tendon reflexes were normal.

At the age of 9 years, the patient received polychemotherapy and allogenic bone marrrow transplantation from her sister for a Philadelphia-chromosome-positive T-lymphoblastic leukaemia without central nervous system involvement. Since then, she is in primary remission.

There was no anaemia, no signs of infection were found, electrolytes, liver and kidney function, coagulation, electrolytes, thyroid hormones, zinc, selenium, ammonia, amino acids in plasma, orotic acid in dried blood and organic acids in urine were all normal at admission.

A native and a contrast-enhanced MRI scan as well as an angio MRI excluded structural abnormalities like CNS-leukaemia, brain tumour, intracranial haemorrhage, sinus thrombosis and hydrocephalus. Lumbar puncture excluded CNS-infection; cerebrospinal fluid opening pressure was normal excluding pseudotumour cerebri. An ophthalmologic examination, as well as a specialist ENT consultation was unrevealing. Physiotherapy did not result in clinical improvement.

Psychosocial stressors explaining the severe symptoms couldn´t be identified.

As we could not find any abnormalities to explain her symptoms we advised her to discontinue minoxidil application and to continue symptomatic therapy with pain killers.

1.5 weeks after discharge, her pain and dizziness had improved and she became free of symptoms after another 2 weeks.

Discussion

After excluding other causes for headache and dizziness like brain tumour, cerebral haemorrhage, CNS infection, pseudotumour cerebri, arterial hyper-/hypotension, migraine, hyperthyroidism, metabolic disorders like ornithinetranscarbamylase (OTC) deficiency and assessment by a psychologist a well as a physiotherapist we supposed that the symptoms in this adolescent were presumably caused by topical treatment with minoxidil. Headache and vertigo are well-known potential side effects of minoxidil treatment [1]. Specialist eye- and ENT-examinations did not reveal a cause for the symptoms observed. We advised to discontinue minoxidil treatment, and symptoms disappeared after a couple of weeks.

Minoxidil is used to stimulate hair growth. It acts as a plasmalemmal potassium channel opener causing hyperpolarization of the cells [3]. Reduction of cytoplasmic calcium in vascular smooth muscle leads to vasodilation. The exact mechanism leading to hair growth is subject to discussion. Blood, oxygen and nutrients reach the follicle and may thereby stimulate hair growth, furthermore minoxidil prolongs the duration of anagen of the hair cycle [4, 5].

Absorption of topical minoxidil is weak with only 0.3-4.5% reaching the circulatory system [5]. Minoxidil is metabolised to its active form minoxidil-sulfate in the scalp by the sulfotransferase SULT 1A1 [6]. This can mediate local vasodilation leading to headache and dizziness.

In a placebo-controlled trial by Lucky et al. headache was reported in 4% of the minoxidil (2%) study population [1]. Furthermore, several cases with cardiovascular side effects like dizziness and palpitations were reported [2, 7]. Onset of symptoms was not reported directly after initiation of treatment but occurred 20- 100 days later, as was the case in our patient.

In summary, minoxidil toxicity has to be considered as a rare cause of headache and dizziness, symptoms can be reversed by discontinuation of therapy. Minoxidil is used by adolescents as over-the counter-self-medication for ‘lifestyle’ purposes to stimulate hair growth. This case report underpins the importance of history taking in patients with headache and dizziness.

References

1. Lucky AW, Piacquadio DJ, Ditre CM, Dunlap F, Kantor I, et al. (2004) A randomized, placebo-controlled trial of 5% and 2% topical minoxidil solutions in the treatment of female pattern hair loss. J Am Acad Dermatol 50:541-553.
2. Satoh H, Morikaw S, Fujiwara C, Terada H, Uehara A, et al. (2000) A case of acute myocardial infarction associated with topical use of minoxidil (RiUP) for treatment of baldness. Jpn Heart J41:519-523.
3. Richer C, Pratz J, Mulder P, Mondot S, Giudicelli JF, et al. (1990) Cardiovascular and biological effects of K+ channel openers, a class of drugs with vasorelaxant and cardioprotective properties. Life Sci 47:1693-1705.
4. Rossi A, Cantisani C, Melis L, Iorio A, Scali E, et al. (2012) Minoxidil use in dermatology, side effects and recent patents. Recent Pat Inflamm Allergy Drug Discov 6:130-136.
5. Shamsaldeen OS, Mubki TA, Shapiro J (2013) Topical agents for hair growth promotion: what is out there? Skin Therapy Lett 18:5-7.
6. Goren A, Castano JA, McCoy J, Bermudez F, Lotti T (2014) Novel enzymatic assay predicts minoxidil response in the treatment of androgenetic alopecia. Dermatol Ther 27: 171-173.
7. Georgala S, Befon A, Maniatopoulou E, Georgala C (2007) Topical use of minoxidil in children and systemic side effects. Dermatology 214:101-102.