Alopecia & the use of Melatonin

Melatonin is a hormone (N-acetyl-5 methoxytryptamine) produced especially at night in the pineal gland. Its secretion is stimulated by the dark and inhibited by light. Tryptophan is converted to serotonin and finally converted to melatonin. The suprachiasmatic nuclei (SCN) of the hypothalamus have melatonin receptors and melatonin may have a direct action on SCN to influence "circadian" rhythms. These are the natural body clocks possessed by all living things to regulate their 24 hour activity cycle.


Melatonin can help to reset the natural body clock and can therefore be used in a variety of diseases that are thought to be associated with loss of this natural rhythm.

Melatonin is a hormone (N-acetyl-5 methoxytryptamine) produced especially at night in the pineal gland. Its secretion is stimulated by the dark and inhibited by light. Tryptophan is converted to serotonin and finally converted to melatonin. The suprachiasmatic nuclei (SCN) of the hypothalamus have melatonin receptors and melatonin may have a direct action on SCN to influence "circadian" rhythms. These are the natural body clocks possessed by all living things to regulate their 24 hour activity cycle.

Melatonin can help to reset the natural body clock and can therefore be used in a variety of diseases that are thought to be associated with loss of this natural rhythm.

Melatonin in alopecia in dogs (1)

Alopecia X is a condition recognized in dogs with double coats such as Pomeranians, Malamutes, Chow chows and Keeshonds. These breeds develop a bilaterally symmetrical alopecia with hyperpigmentation of the skin that is not caused by an imbalance in thyroid or steroid hormones. Diagnosis is made on the basis of clinical signs, diagnostic rule outs of other diseases such as hypothyroidism and hyperadrenocorticism and biopsies. Different management strategies have been suggested. Neutering is recommended by some dermatologists when animals are entire. Melatonin has been shown to result in partial of complete hair regrowth in 40% of animals. The dosage is variable and can be increased depending on response to therapy. Melatonin at a dose of 3mg once or twice daily has been shown to be useful but can be doubled.

Melatonin in alopecia in dogs (2)

Canine recurrent (seasonal ) flank alopecia is a skin disorder of unknown aetiology that is characterized by episodes of truncal hair loss on a seasonal basis each year. It is thought to be related to changing photoperiods and the dog’s inability to adapt to this appropriately within a modern environment. It is most commonly seen in boxers (50% of all cases) but is also commonly seen in Airedale terriers, English bulldogs, Dobermans, Mastiffs and many other short coated breeds. Most dogs show signs between November and March each year. Diagnosis is made on the basis of clinical signs especially in predisposed breeds, diagnostic rule outs of other diseases such as hypothyroidism and hyperadrenocorticism and biopsies. The disease is benign and in many cases hair will grow back without any therapy as the photoperiod changes. However in some dogs hair loss is severe and does not grow back. Melatonin has been shown to help with hair loss in dogs with a recurrent history of alopecia every year and has been shown to increase hair regrowth in 50-75% of cases

Melatonin as a treatment for sleep disorders.

Restlessness at night is something experienced by people and pets. This may be due to a loss of natural sleep patterns or could be due to noise phobias or due to the loss of natural triggers that can occur in blind animals. Melatonin given in the evening mimics the natural pulsatile release of this hormone normally triggered by dark and can help to regulate these normal patterns to allow a more settled night.