Taking recommended doses of several drugs together, which individually do not cause impairment, may combine to bring on drowsiness or other impairment. This could be more pronounced in an elderly person whose renal function is less efficient than a younger persons.Thus, there are situations when a person may be impaired, but still legally allowed to drive, and becomes a potential hazard to themselves and other road users. Pedestrians or cyclists are affected in the same way and can similarly jeopardize themselves or others when on the road. Road design
A 1985 US study showed that about 34% of serious crashes had contributing factors related to the roadway or its environment. Most of these crashes also involved a human factor. The road or environmental factor was either noted as making a significant contribution to the circumstances of the crash, or did not allow room to recover. In these circumstances, it is frequently the driver who is blamed rather than the road; those reporting the collisions have a tendency to overlook the human factors involved, such as the subtleties of design and maintenance that a driver could fail to observe or inadequately compensate for.Research has shown that careful design and maintenance, with well-designed intersections, road surfaces, visibility and traffic control devices, can result in significant improvements in collision rates. Individual roads also have widely differing performance in the event of an impact.
Bexarotene, sold under the brand Targretin, is an antineoplastic (anti-cancer) agent used for the treatment of cutaneous T cell lymphoma (CTCL). It is a third-generation retinoid.It was approved by the U.S. Food and Drug Administration (FDA) in December 1999, and the European Medicines Agency (EMA) in March 2001. It is available as a generic medication. Medical uses
Bexarotene is indicated for the treatment of cutaneous manifestations of cutaneous T-cell lymphoma in people who are refractory to at least one prior systemic therapy (oral) and for the topical treatment of cutaneous lesions in patients with CTCL who have refractory or persistent disease after other therapies or who have not tolerated other therapies (topical).It has been used off-label for non-small cell lung cancer and breast cancer. Contraindications
Known contraindications include:

Adverse effects
Overall the most common adverse effects are skin reactions (mostly itchiness and rashes), leucopenia, headache, weakness, thyroid anomalies (which seem to be mediated by RXR-mediated downregulation of thyroid stimulating hormone) and blood lipid anomalies such as hypercholesterolaemia (high blood cholesterol) and hyperlipidaemia, hypothyroidism. Interactions
Its plasma concentration may be increased by concomitant treatment with CYP3A4 inhibitors such as ketoconazole. It may also induce CYP3A4, and hence CYP3A4 substrates like cyclophosphamide may have their plasma concentrations reduced. Likewise consumption of grapefruit juice might increase bexarotenes plasma concentrations, hence potentially altering its therapeutic effects. Mechanism
Bexarotene is a retinoid that selectively activates retinoid X receptors (RXRs), as opposed to the retinoic acid receptors, the other major target of retinoic acid (the acid form of vitamin A).