Drugs and supplements
Some medications have side effects that result in hair loss. Drugs are given to patients to treat cancer, depression, heart conditions, high blood pressure, hypertension, gout [5], and arthritis [6]. Any abnormal hair loss noticed should be reported to the medical doctor immediately when using drugs like this. Also, make sure you tell doctors the drugs you react to so they know what other medication to give to prevent hair loss.
Cancer treatments
Most times, when people undergo chemotherapy [7] or receive radiation therapy sessions on the head or neck, they lose some or all of there within a few days of the treatment. The hair begins to regrow after months of concluding chemotherapy, and doctors give medication to assist hair growth [8]. The hair never regrows in some cases.
Conclusion
The most important thing when considering hair loss is the cause because, without adequate knowledge of the cause and efficient diagnoses, it is impossible to give proper treatment to patients.
References
[1] http://www.healthline.com/
[2] http://www.mayoclinic.org/
[3] http://www.nationaleczema.org/
[4] http://www.psoriasis.org/
[5] http://www.psoriasis.org/
[6] http://www.healthline.com/
[7] http://www.webmd.com/
[8] http://www.nyulangone.org/