Spas with reservation required

Hot Springs, Arkansas

A combined day spa and med spa in Hot Springs offering massages, facials, laser treatments and lunch-inclusive packages by reservation.

Sopot, Pomerania

A medical resort spa in Sopot built around local brine and mud treatments, open to hotel guests by reservation rather than day visitors.

Piešťany, Trnava Region

Spa Irma on Piešťany's spa island offers historic mud and mirror thermal pools, a hydrotherapy circuit and a 60-treatment medical spa menu, adults only.

Tbilisi

A medical spa in Old Tbilisi built around natural sulfur-mineral water and volcanic mud, operating since 1938, open daily 10am–9pm.

Houston, Texas

A 20,000-square-foot hotel spa in Houston's Westside offering a biohacking facial machine, hydrotherapy circuit and co-ed relaxation lounge, by appointment

Aix-les-Bains, Auvergne-Rhône-Alpes

Medical thermal baths in Aix-les-Bains treating respiratory and oral mucosal conditions with sulfur-rich water, mostly through prescribed multi-day cures.

San Diego, California

A La Jolla medical spa specializing in lymphatic drainage, colon hydrotherapy and detox treatments, open since 1993, adults only, by reservation.

Rogaška Slatina, Savinjska

A reservation-only medical spa and clinic in Rogaška Slatina combining diagnostics, wellness treatments and the region's magnesium-rich Donat mineral water.

Hévíz, Zala

A natural thermal lake and medical spa in Hévíz, Hungary, offering mud and weight baths, massage and physiotherapy, open daily 9:00–18:30.