Introduction
When we talk about the relationship between drugs and hair, we can refer to two very distinct situations: one in which we want to indicate all those drugs used to combat hair loss and another in which, instead, we want to indicate drugs which can cause, or in any case favor, hair loss.
Anti-hair loss drugs
The effectiveness of drugs dedicated to the treatment of alopecia (hair loss) depends on the causes that have produced the thinning. In general, these medicines produce the more satisfactory results the lower the severity of the alopecia and the earlier they are taken. pharmaceuticals and foods - this includes pharmaceutical products such as minoxidil and finasteride.
Minoxidil
Minoxidil is used in the treatment of androgenetic and aerated alopecia. The former, also known as common baldness, is the most frequent form especially in men and is due to hormonal factors that are added to an "innate genetic predisposition; it leads to a generalized and progressive "fall" of the hair, generally sparing the nape and the lower part of the temples (areas available for a possible autotransplant). In "alopecia areata, on the other hand, there is a" sudden hair loss confined to small roundish patches; the causes of origin, in this case, are different, with an "important autoimmune and genetic component.
Minoxidil (Regaine®, Aloxidil®) is available in foam or lotions at 2 and 5%, to be distributed on the scalp a couple of times a day; positive results can be recorded after three or four months of regular treatment, but they tend to disappear when its use is discontinued. For this reason, if satisfactory regrowth is not achieved after six months of regular use, the use of minoxidil can be suspended.
The most common side effects include skin irritation, with itching, contact dermatitis, dry scalp and increased flaking.
Finasteride
Finasteride (Propecia®) is an anti-hair loss drug approved for the treatment of androgenetic alopecia. It is taken in the form of tablets and in a good percentage of cases it stops the fall, stimulating the regrowth of hair produced by follicles not yet completely atrophied. in this case, the beneficial effects become evident after about 12 weeks, and are subordinated to the regular and constant use of the product.
The drug works by inhibiting the conversion of testosterone into dihydrotestosterone especially in the hair follicles, eliminating an important risk factor for baldness.
Finasteride is also well tolerated by the patient and the rare side effects mainly affect the sexual sphere, with a slight decrease in desire, erectile dysfunction and reduced ejaculate volume. The use of finasteride is strongly contraindicated in women of childbearing age, for the serious damage it can cause to the male fetus.
Corticosteroids
Corticosteroids are also used as drugs against hair loss, in particular, in the case of androgenetic alopecia and alopecia areata.
Except for particularly severe cases in which they are administered orally or parenterally, in the treatment of alopecia, corticosteroids are administered topically.
Their use against hair loss is justified by their anti-inflammatory and immunosuppressive properties.
Among the active ingredients most used in this field, we mention betamethasone (Ecoval®) and triamcinolone (Kenacort®).
When used topically, the main undesirable effects caused by the aforementioned active ingredients consist of skin irritation, burning and / or pain at the application site.
Other Drugs
Other drugs that can help in the fight against hair loss include dutasteride (which acts in a similar way to finasteride), ketoconazole (a drug for the treatment of fungal infections that also slows down the synthesis of dihydrotestosterone as well as of the above), cyclosporine and antraline (used in the treatment of alopecia areata), azelaic acid and estrone sulfate (used in the treatment of female androgenetic alopecia).
Fall-promoting drugs
Several medications can cause temporary hair loss, amplify the existing problem or even cause permanent baldness. Leaving aside the medicinal preparations (chemotherapy) and techniques (such as radiation therapy) used in the oncology field, among the drugs that can cause or accelerate hair loss we remember:
- Isotreonin and other drugs derived from vitamin A (used mainly in the treatment of acne).
- Warfarin (Coumadin®) and heparin injections (oral and non-oral anticoagulants).
- Clofibrate and gemfibrozil (lipid-lowering agents, useful for lowering cholesterol and triglycerides).
- Anticonvulsants.
- Various antidepressants, including fluoxetine (Prozac®) and imipramine.
- Amphetamines (sometimes used unconsciously to promote weight loss).
- Some antifungals.
- Beta-blocking antihypertensives, such as timolol, atenolol, metoprolol, nadolol and propranolol.
- L "allopurinol (used in the treatment of gout).
- Anabolic steroids and hormonal therapies of various types (prednisone, testosterone and other androgens, HRT, birth control pills).
- Rheumatoid arthritis drugs and NSAIDs, such as naproxen, indomethacin and methotrexate.
- Medicines for the treatment of thyroid dysfunction.
- Medicines to treat Parkinson's disease, such as levodopa.
- Anti-ulcer drugs, such as cimetidine, ranitidine and famotidine.
Mechanism of action
Each of the aforementioned drugs can cause, favor or accelerate hair loss with its own mechanism of action. In any case, they act by interrupting the natural cycle of hair growth, favoring hair loss.
The type of fall (telogen effluvium or anagen effluvium) caused by the drugs depends on the active ingredient used, the dosage at which it is taken and the sensitivity of each individual to the same drug.
When to worry?
As mentioned, not all patients who take the aforementioned drugs can experience hair loss, since this phenomenon depends on a large variety of factors, including individual sensitivity to the drug used.
Generally, 40 to 120 hairs are lost within a day; this is considered an absolutely normal phenomenon that is part of the normal life cycle of the hair.
On the contrary, when you are witnessing a very intense and marked hair loss, you should worry and contact your doctor, or immediately request a consultation with a specialist. In this regard, it is of fundamental importance to inform the doctor of one's state of health, making him participate in the pharmacological therapies that are being followed (for more information: How Many Hairs Fall in a Day?).
